Algebra · Textbook solutions
Quadratic Equations
Every solved example, exercise, and miscellaneous question — in the order the textbook teaches them. · 135 questions
Standard form of quadratic equation
4 q
Solved Examples
Worked · 4
- Decide which of the following are quadratic equations ?Standard form of quadratic equation SolvedEx.1 (1)
- Standard form of quadratic equation SolvedEx.1 (2)
- Standard form of quadratic equation SolvedEx.1 (3)
- Standard form of quadratic equation SolvedEx.1 (4)
Roots of a quadratic equation
1 q
Solved Example
Worked · 1
- Roots of a quadratic equation SolvedEx.1check whether (i) , (ii) are solutions of the equations.
Practice Set 2.1
17 q
- Ex 2.1 Q.1Write any two quadratic equations.
- Decide which of the following are quadratic equations.Ex 2.1 Q.2 (1)
- Ex 2.1 Q.2 (2)
- Ex 2.1 Q.2 (3)
- Ex 2.1 Q.2 (4)
- Ex 2.1 Q.2 (5)
- Ex 2.1 Q.2 (6)
- Write the following equations in the form , then write the values of for each equation.Ex 2.1 Q.3 (1)
- Ex 2.1 Q.3 (2)
- Ex 2.1 Q.3 (3)
- Ex 2.1 Q.3 (4)
- Ex 2.1 Q.3 (5)
- Ex 2.1 Q.3 (6)
- Determine whether the values given against each of the quadratic equation are the roots of the equation.Ex 2.1 Q.4 (1),
- Ex 2.1 Q.4 (2),
- Ex 2.1 Q.5Find if is a root of equation .
- Ex 2.1 Q.6One of the roots of equation is . Complete the following activity to find the value of ''. Solution : is a root of quadratic equation Put in the equation.
Solutions of a quadratic equation by factorisation
5 q
Solved Examples
Worked · 5
- Solve the following quadratic equations by factorisation.Solutions of a quadratic equation by factorisation SolvedEx.1 (1)
- Solutions of a quadratic equation by factorisation SolvedEx.1 (2)
- Solutions of a quadratic equation by factorisation SolvedEx.1 (3)
- Solutions of a quadratic equation by factorisation SolvedEx.1 (4)
- Solutions of a quadratic equation by factorisation SolvedEx.1 (5)
Practice Set 2.2
12 q
- Solve the following quadratic equations by factorisation.Ex 2.2 Q.1 (1)
- Ex 2.2 Q.1 (2)
- Ex 2.2 Q.1 (3)
- Ex 2.2 Q.1 (4)
- Ex 2.2 Q.1 (5)
- Ex 2.2 Q.1 (6)
- Ex 2.2 Q.1 (7)to solve this quadratic equation by factorisation, complete the following activity. Solution : or or and are roots of the equation.
- Ex 2.2 Q.1 (8)
- Ex 2.2 Q.1 (9)
- Ex 2.2 Q.1 (10)
- Ex 2.2 Q.1 (11)
- Ex 2.2 Q.1 (12)
Solution of a quadratic equation by completing the square
2 q
Solved Examples
Worked · 2
- Solution of a quadratic equation by completing the square SolvedEx.1Solve :
- Solution of a quadratic equation by completing the square SolvedEx.2Solve :
Practice Set 2.3
6 q
- Solve the following quadratic equations by completing the square method.Ex 2.3 (1)
- Ex 2.3 (2)
- Ex 2.3 (3)
- Ex 2.3 (4)
- Ex 2.3 (5)
- Ex 2.3 (6)
Formula for solving a quadratic equation
5 q
Solved Examples
Worked · 5
- Solve quadratic equations using formula.Formula for solving a quadratic equation SolvedEx.1
- Formula for solving a quadratic equation SolvedEx.2
- Formula for solving a quadratic equation SolvedEx.3
- Formula for solving a quadratic equation SolvedEx.4
- Formula for solving a quadratic equation SolvedEx.5
Practice Set 2.4
10 q
- Compare the given quadratic equations to the general form and write values of .Ex 2.4 Q.1 (1)
- Ex 2.4 Q.1 (2)
- Ex 2.4 Q.1 (3)
- Solve using formula.Ex 2.4 Q.2 (1)
- Ex 2.4 Q.2 (2)
- Ex 2.4 Q.2 (3)
- Ex 2.4 Q.2 (4)
- Ex 2.4 Q.2 (5)
- Ex 2.4 Q.2 (6)
- Ex 2.4 Q.3With the help of the flow chart given below solve the equation using the formula. Flow chart : compare equations and find the values of Find value of Write formula to solve quadratic equation Substitute values of and find roots.
Nature of roots of a quadratic equation
4 q
Solved examples
Worked · 4
- Nature of roots of a quadratic equation SolvedEx.1Find the value of the discriminant of the equation
- Determine nature of roots of the quadratic equations.Nature of roots of a quadratic equation SolvedEx.2 (i)
- Nature of roots of a quadratic equation SolvedEx.2 (ii)
- Nature of roots of a quadratic equation SolvedEx.3
The relation between roots of the quadratic equation and coefficients
3 q
Solved examples
Worked · 3
- The relation between roots of the quadratic equation and coefficients SolvedEx.1If and are the roots of the quadratic equation , then find and .
- The relation between roots of the quadratic equation and coefficients SolvedEx.2The difference between the roots of the equation is 7 find .
- The relation between roots of the quadratic equation and coefficients SolvedEx.3If and are the roots of then find - (i) (ii) .
To obtain a quadratic equation having given roots
1 q
Solved examples
Worked · 1
- To obtain a quadratic equation having given roots SolvedEx.1Obtain the quadratic equation if roots are .
Practice Set 2.5
18 q
- Activity : Fill in the gaps and complete.Ex 2.5 Q.1 (1)A flow chart runs from the box "Quadratic equation " to two boxes, "" and "", and from each of those an arrow points to an empty box under the heading "Nature of roots". Fill in the two empty boxes.
- Ex 2.5 Q.1 (2)A flow chart has the box "Sum of roots " on the left and "Product of roots " on the right, both pointing to a central box "Quadratic equation . . . . . . . .". Fill in the central box.
- Ex 2.5 Q.1 (3)If , are roots of quadratic equation, a flow chart runs from the box "" to two boxes, "" and "". Fill in the two boxes.
- Find the value of discriminant.Ex 2.5 Q.2 (1)
- Ex 2.5 Q.2 (2)
- Ex 2.5 Q.2 (3)
- Determine the nature of roots of the following quadratic equations.Ex 2.5 Q.3 (1)
- Ex 2.5 Q.3 (2)
- Ex 2.5 Q.3 (3)
- Form the quadratic equation from the roots given below.Ex 2.5 Q.4 (1)0 and 4
- Ex 2.5 Q.4 (2)3 and
- Ex 2.5 Q.4 (3)
- Ex 2.5 Q.4 (4)
- Ex 2.5 Q.5Sum of the roots of a quadratic equation is double their product. Find if equation is
- , are roots of find,Ex 2.5 Q.6 (1)
- Ex 2.5 Q.6 (2)
- The roots of each of the following quadratic equations are real and equal, find .Ex 2.5 Q.7 (1)
- Ex 2.5 Q.7 (2)
Application of quadratic equation
2 q
Solved examples
Worked · 2
- Application of quadratic equation SolvedEx.1There is a rectangular onion storehouse in the farm of Mr. Ratnakarrao at Tivasa. The length of rectangular base is more than its breadth by 7 m and diagonal is more than length by 1 m. Find length and breadth of the storehouse.
- Application of quadratic equation SolvedEx.2A train travels 360 km with uniform speed. The speed of the train is increased by 5 km/hr, it takes 48 minutes less to cover the same distance. Find the initial speed of the train.
Practice Set 2.6
10 q
- Ex 2.6 Q.1Product of Pragati's age 2 years ago and 3 years hence is 84. Find her present age.
- Ex 2.6 Q.2Sum of squares of 2 consecutive natural even numbers is 244; find the numbers.
- Ex 2.6 Q.3In the orange garden of Mr. Madhusudan there are 150 orange trees. The number of trees in each row is 5 more than that in each column. Find the number of trees in each row and each column with the help of following flow chart. Flow chart : No. of trees in a column is No. of trees in row Total no. of trees Frame quadratic equation Find No. of trees in column no. of trees in a row.
- Ex 2.6 Q.4Vivek is older than Kishor by 5 years. The sum of the reciprocals of their ages is . Find their present ages.
- Ex 2.6 Q.5Suyash scored 10 marks more in second test than that in the first. 5 times the score of the second test is the same as square of the score in the first test. Find his score in the first test.
- Ex 2.6 Q.6Mr. Kasam runs a small business of making earthen pots. He makes certain number of pots on daily basis. Production cost of each pot is ₹ 40 more than 10 times total number of pots, he makes in one day. If production cost of all pots per day is ₹ 600, find production cost of one pot and number of pots he makes per day.
- Ex 2.6 Q.7Pratik takes 8 hours to travel 36 km downstream and return to the same spot. The speed of boat in still water is 12 km. per hour. Find the speed of water current.
- Ex 2.6 Q.8Pintu takes 6 days more than those of Nishu to complete certain work. If they work together they finish it in 4 days. How many days would it take to complete the work if they work alone.
- Ex 2.6 Q.9If 460 is divided by a natural number, quotient is 6 more than five times the divisor and remainder is 1. Find quotient and diviser.
- Ex 2.6 Q.10In the adjoining fig. is a trapezium AB CD and its area is 33 cm. From the information given in the figure find the lengths of all sides of the . Fill in the empty boxes to get the solution. Figure : is drawn with AB the shorter parallel side on top and DC the longer parallel side at the bottom. M is the foot of the perpendicular from A to DC, so . The printed labels are AB , AM , BC , DC ; AD and BC carry matching double tick marks, so AD BC. Solution : is a trapezium. AB CD or or But length is never negative. AB , CD , AD BC
Problem Set 2
35 q
- Choose the correct answers for the following questions.PS2 Q.1 (1)Which one is the quadratic equation ?
- A.
- B.
- C.
- D.
- A.
- PS2 Q.1 (2)Out of the following equations which one is not a quadratic equation ?
- A.
- B.
- C.
- D.
- A.
- PS2 Q.1 (3)The roots of are real and equal, find .
- A.0
- B.4
- C.0 or 4
- D.2
- A.
- PS2 Q.1 (4)For find the value of the discriminant.
- A.
- B.17
- C.
- D.
- A.
- PS2 Q.1 (5)Which of the following quadratic equations has roots 3, 5 ?
- A.
- B.
- C.
- D.
- A.
- PS2 Q.1 (6)Out of the following equations, find the equation having the sum of its roots .
- A.
- B.
- C.
- D.
- A.
- PS2 Q.1 (7)which of the following statement is true for this given equation ?
- A.Real and uneual roots
- B.Real and equal roots
- C.Roots are not real
- D.Three roots.
- A.
- PS2 Q.1 (8)One of the roots of equation is 2; find .
- A.
- B.
- C.
- D.2
- A.
- Which of the following equations is quadratic ?PS2 Q.2 (1)
- PS2 Q.2 (2)
- PS2 Q.2 (3)
- Find the value of discriminant for each of the following equations.PS2 Q.3 (1)
- PS2 Q.3 (2)
- PS2 Q.3 (3)
- PS2 Q.4One of the roots of quadratic equation is , find .
- Two roots of quadratic equations are given ; frame the equation.PS2 Q.5 (1)10 and
- PS2 Q.5 (2)and
- PS2 Q.5 (3)0 and 7
- Determine the nature of roots for each of the quadratic equation.PS2 Q.6 (1)
- PS2 Q.6 (2)
- PS2 Q.6 (3)
- Solve the following quadratic equations.PS2 Q.7 (1)
- PS2 Q.7 (2)
- PS2 Q.7 (3)
- PS2 Q.7 (4)
- PS2 Q.7 (5)
- PS2 Q.7 (6)
- PS2 Q.8Find if has real and equal roots.
- PS2 Q.9The sum of two roots of a quadratic equation is 5 and sum of their cubes is 35, find the equation.
- PS2 Q.10Find quadratic equation such that its roots are square of sum of the roots and square of difference of the roots of equation
- PS2 Q.11Mukund possesses ₹ 50 more than what Sagar possesses. The product of the amount they have is 15,000. Find the amount each one has.
- PS2 Q.12The difference between squares of two numbers is 120. The square of smaller number is twice the greater number. Find the numbers.
- PS2 Q.13Ranjana wants to distribute 540 oranges among some students. If 30 students were more each would get 3 oranges less. Find the number of students.
- PS2 Q.14Mr. Dinesh owns an agricultural farm at village Talvel. The length of the farm is 10 meter more than twice the breadth. In order to harvest rain water, he dug a square shaped pond inside the farm. The side of pond is of the breadth of the farm. The area of the farm is 20 times the area of the pond. Find the length and breadth of the farm and of the pond
- PS2 Q.15A tank fills completely in 2 hours if both the taps are open. If only one of the taps is open at the given time, the smaller tap takes 3 hours more than the larger one to fill the tank. How much time does each tap take to fill the tank completely ?