Question

(x+a)^2 -7 = x^2 +10x +b

Work out the value of a and b.

Answer 1

(x+a)²-7=x²+10x+b

simplifying,we get

x²+2ax+a²-7=x²+10x+b

the coefficient of x on both sides should be equal

therefore

2a=10

a=10/2=5

also for b

a²-7=b

5²-7=25-7=b

b=18

a=5