Chapter 4: Quadratic Equation, Assignment 1

Q1. Solving quadratic equations by factorisation

1. 5a2 + 15a = 0.
2. x2 + 16 = 10x
3. 18x2 – 3x = 6
4. 50x2 = 72
5. x2 – 13x = 30
6. 20x2 – 130x = –200
7. 4x(2x + 3) = 36
8. (x + 3)2 – (2x – 1)2 = 0
9. x(x + 4) = 32
10. (2x – 5)(x + 1) = –12x
11. (x – 7)2 + x2 = (x + 1)2
12. 3√2x2 – 13x + 5√2 = 0

Q2. Solving quadratic equations by Completing the square

1. x2 + 2x + 1 = 0
2. x2 - 4x + 4 = 0
3. x2 - 6x + 2 = 0
4. x2 + 10x − 4 = 0
5. 4x2 + x = 3
6. 2 x 2 – 3 x + 4 = 0
7. –2x2 – 12x – 9 = 0
8. –3x2 – 18x – 35 = 0
9. 5x2 +20x +32 = 0
   

Q 3.

Q 4. The quadratic equation, whose roots are 2 + √3, 2 – √3 , will be _____

1. x2 + 4x + 1 = 0  (b) x2 – 4x + 1 = 0              

   (c) x2 + 4x – 1 = 0    (d) x2 – 4x – 1 = 0

Q 5. Find the quadratic equation having roots (1 + √2) and (1 – √2).

Q 6. Is x = −3 a solution of the equation x2 – 3x + 7 = 0 ?

Q 7. Show that x = –2 is a solution of the equation 2x2 – 4x – 16 = 0

Q 8.

Q 9. Find the value of

Q 10. If 2 is a root of the equation ax2 + ax + 2 = 0 and x2 – x – b = 0 then find a/b.

Q 11. If x = 1/3 is a solution to the equation 3x2 – 2kx + 5 = 0 find k.

Q 12. Solve