Question

a) What number is to be added to x2+6x to get a perfect square
B) if x2+ax+16 is a pperfect square which number is 'a'
C) if x2+ax+b is a perfect square prove that a2=4b

Answer 1

Answer:

a) ans : 3

b) ans:8

c) ans:

a2-4b=0 → formula method ∆ = 0 for perfect square(ax2+bx+c=0,, for b2-4ac=0)

hence a2=4b

Answer 2

Answer:

a- 9

b-8

c- (x+√b)^2 = x^2 + 2.x.√b + b

so here

a = 2. √b

thus

2a = 4b.