tolong bantu no.11 sama 12 ya

11). f(x) = 3x + 2
f(a) = 38
f(a) = 3a + 2
38 = 3a + 2
3a = 38 - 2
3a = 36
a = 36 : 3
a = 12

12). f(x) = 1/2(x + 3)
f(a) = 4
f(a) = 1/2(a + 3)
4 = 1/2(a + 3)
4 x 2 = a + 3
8 = a + 3
a = 8 - 3
a = 5

no. 11
3x+2 = 38
3x     = 38-2
x       = 36÷3
x       = 12 (C)

no. 12
1/2x+1,5 = 4
1/2x        = 4-1,5
x             = 2,5 × 2 ÷ 1
x             = 5 (B)