Question

find the root of the quadratic equation using the completing square method 5 x square - 7 x - 6 =0

Answer 1

Hello

5xsq. - 7x - 6 =0

x2 - 7/5x - 6/5 = 0 divide by 5

x2 - 7/5x + 7/5sq *1/2) - 6/5 =0 you can multiple 1/2 into the middle term to get b2 of a+b whole sq.

(x- 7/10)2 =7/10sq. + 6/5

(x - 7/10)2 = 49/100 + 6/5

(x - 7/10)2 = 49 + 6*20/100

(x - 7/10)2 = 49 +120/100

(x - 7/10)2 = 169/100

cancel the sq of from both the sides

x - 7/10 = 13/10 (13/10 can be + or -)

x = 13 + 7/10 = 20/10  = 2 and x = 7 - 13/10 = -6/10 = -3/5

the root are 2 and -3/5