jika f(x)=2x+5 dan g(x)=x²+2 dan f(x)=9(x) maka nilai x adalah…

f(x) = 2x + 5
g(x) = x² + 2
f(x) = g(x)
2x + 5 = x² +2
x² + 2 - 2x - 5 = 0
x² - 2x - 3 = 0
(x + 1)(x - 3) = 0
x + 1 = 0 atau x - 3 = 0
x = -1 atau x = 3

fx = gx
2x + 5 = x² + 2
-x² + 2x - 2 + 5 = 0
-x² + 2x + 3 = 0
(x + 1 )(-x + 3) = 0
x = -1      -x + 3 = 0 | -x = -3 + 0 | x = 3
HP = (-1,3)