suatu fungsi f di rumus kan dengan d(x)= ax+b diketahui f(3)=15 dan f(-2)=-20. nilai a dan b berturut-turut adalah...

f(x) = ax + b

f(3) = a(3) + b = 3a + b = 15
f(-2) = a(-2) + b = -2a + b = -20
_______________________–
5a = 35
a = 7

3a + b = 15
3(7) + b = 15
21 + b = 15
b = -6

f(3) = 3a + b = 15
f(-2) = -2a + b = -20
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5a = 35
a = 35÷5 = 7
3a + b = 15
3(7) + b = 15
21 + b = 15
b = 15 - 21 = -6

a, b = 7, -6