Question

Mohon jawab ya ...persiapan ulangan besok

Answer 1

4. f(x) = ax+b

f(-1) = -a+b = 5
f(3) = 3a+b = 3
_____________
-a+b = 5
3a+b = 3
________-
-4a = 2
a = 2/-4
a = -½

•> -a+b = 5
-(-½)+b = 5
½+b = 5
b = 5-½
b = 10/2-½
b = 9/2

# nilai a = -½, nilai b = 9/2

# rumus fungsi f(x) = -½x+9/2

# nilai f(-4) = -½.(-4)+9/2 = -4/-2+9/2 = 4/2+9/2 = 13/2

nilai f(-9) = -½.(-9)+9/2 = -9/-2+9/2 = 9/2+9/2 = 18/2 = 9

# nilai k,
f(k) = -½k+9/2 = 7
-½k = 7-9/2
-½k = 14/2-9/2
-½k = 5/2
k = 5/2 : -½
k = 5/2×-2
k = -10/2 = -5

maaf cuma bisa bantu 1 soal