Question

Which is f(5) for the function 2x2 + 2x - 3?

Answer 1

Replace every x you see with 5 and do the math.

f(x) = 2x^2 + 2x - 3

f(5) = 2(5)^2 + 2(5) - 3

f(5) = 2(25) + 10 - 3

f(5) = 50 + 10 - 3

f(5) = 60 - 3

f(5) = 57

Answer 2

f(5)= 2x2+2(5)-3
f(5)=11