Practice Set 2.3

- x^2 + x - 20 = 0 Solve the following quadratic equation by completing the square…
- x^2 + 2x - 5 = 0 Solve the following quadratic equation by completing the square…
- m^2 - 5m = -3 Solve the following quadratic equation by completing the square method.…
- 9y^2 - 12y + 2 = 0 Solve the following quadratic equation by completing the square…
- 2y^2 + 9y + 10 = 0 Solve the following quadratic equation by completing the square…
- 5x^2 = 4x + 7 = 0 Solve the following quadratic equation by completing the square…

###### Practice Set 2.3

Question 1.Solve the following quadratic equation by completing the square method.

x2 + x – 20 = 0

Answer:

⇒

⇒

⇒

⇒

⇒

⇒

⇒

⇒

⇒

⇒

Question 2.

Solve the following quadratic equation by completing the square method.

x2 + 2x – 5 = 0

Answer:

⇒

⇒

⇒

⇒

⇒

⇒

⇒

⇒

Question 3.

Solve the following quadratic equation by completing the square method.

m2 – 5m = -3

Answer:

⇒ (Adding and Subtracting )

⇒

⇒

⇒

⇒

⇒

⇒

⇒

⇒

Question 4.

Solve the following quadratic equation by completing the square method.

9y2 – 12y + 2 = 0

Answer:

(3y)2 - 2 × 3y × 4 + (4)2 - (4)2 + 2 = 0

(3y)2 - 2 × 3y × 4 + (4)2 - 16 + 2 = 0

(3y - 4)2 - 14 = 0

(3y - 4)2 = 14

3y - 14 = ±√14

3y = 14 ± √14

y = (14 ± √14)/3

Question 5.

Solve the following quadratic equation by completing the square method.

2y2 + 9y + 10 = 0

Answer:

Steps involved in solving quadratic equation by completing the square method are -

1. Making the first variable free of coefficient

Dividing by the coefficient of 2, we get,

⇒

2. The coefficient of linear variable(variable with degree 1) is then squared and then added and subtracted from the equation.

⇒

3. Take out the terms following the formula (a + b)2 = a2 + b2 + 2 a b

⇒

⇒

Question 6.

Solve the following quadratic equation by completing the square method.

5x2 = 4x + 7 = 0

Answer:

⇒

⇒ (Adding and Subtracting )

⇒

⇒

⇒

⇒