Caranya gimana nih bantuin dong

No 1 yg A saya lupa
B. f(3) = 3^2 + 3(3) – 5 = 13
f(-3) = (-3)^2 + 3(-3) – 5 = -5
C. f(x) = x^2 + 3x – 5 = 5
f(x) = x^2 + 3x – 10 = 0
f(x) = (x + 5) (x – 2)
x = -5 dan x = 2