Answer:
15
Step-by-step explanation:
If -3 and -5 are the x intercepts, then (x+3) and (x+5) are factors
f(x) = (x+3)(x+5)
Expand
f(x) = x² + 5x + 3x + 3(5)
f(x) = x²+8x + 15
Equate x²+8x + 15 with x²+8x
x²+8x + 15 = x²+8x + b
On comparing
15 = b
Swap sides
b = 15
Hence the constant term is 15
