Question

If (ax+2)(x+b) = 3x^2 + 5x + c for all values of x, what is the value of c?

Answer 1

c=2

Explanation:

(ax+2)(x+b) = ax^2+2x+abx+2b = ax^2+(2+ab)x+2b

Given, ax^2+(2+ab)x+2b = 3x^2+5x+c

a=3

2+ab=5 => 2+3b=5 => 3b=5-2=3 => b=1

2b=c => c=2*1 = 2

So, c=2