fungsi f (×)= 2×-3 .jika f (b) = 5 , nilai b adalah

f(x) = 2x - 3
f(b) = 2b - 3

f(b) = 5
2b - 3 = 5
2b = 5 + 3
2b = 8
b = 8 : 2
b = 4

f (x) = 2x - 3
5 = 2x - 3
-2x = -5 - 3
-2x = -8
x = -8 ÷ -2
x = 4