2x2 + 10x + 7 = 0
Bring the coefficient of x2 to 1 by dividing throughout by 2.
2(x2 + 5x + 7/2) = 0 Note : (x + h)2 = x2 + 2hx + h2...so h = half the coefficient of x
2(x + 5/2)2 - 22/4 = 0
2(x + 5/2)2 - 11/2 = 0
Note : 2 x (5/2)2 = 2 x 25/4 = 50/4 but we only require a value of 7 = 28/4 so we need to subtract 22/4
Bring the coefficient of x2 to 1 by dividing throughout by 2.
2(x2 + 5x + 7/2) = 0 Note : (x + h)2 = x2 + 2hx + h2...so h = half the coefficient of x
2(x + 5/2)2 - 22/4 = 0
2(x + 5/2)2 - 11/2 = 0
Note : 2 x (5/2)2 = 2 x 25/4 = 50/4 but we only require a value of 7 = 28/4 so we need to subtract 22/4