Question

Using completing the square method in quadratic equation 5x²+ 11x + 2=0​

Answer 1

Answer:

x= 1/5 or -2

Step-by-step explanation:

5x² +11x +2= 0

(Divide through by the coefficient of x²)

5x²/5 + 11x/5 + 2/5 = 0/5

x² + 11x/5 + 2/5 = 0

(take the constant to the other side)

x² + 11x/5 = -2/5

(Add 1/2 of the coefficisint of x all square to both sides)

x² + x + (11/5 × 1/2)² = -2/5 + (11/5 × 1/2)²

x² + x + (11/10)² = -2/5 + (11/10)²

x² + x + (11/10)² = -2/5 + 121/100

(eliminate x )

x² + (11/10)² = (20(-2) + 121 ) ÷ 100

(x + 11/10 )² = (-40 + 121) ÷ 100

(x + 11/10 )² = 81/100

(square both sides)

x + 11/ 10 =√(81/100)

x + 11/10 = 9/10

x = -11/10 +or- 9/10

x = -11/10 + 9/10 or -11/10 - 9/10

x = (-11 + 9) ÷ 10 or (-11-9) ÷ 10

x = -2/ 10 or -20/10

x = -1/5 or -2