Fungsi f(x) = ax+ b jika f (-2 ) = 27 dan f (5) = -8 maka nilai a+b adalah

[tex]f(x) = ax + b \\ f( - 2) = 27 \\ f(5) = - 8 \\ \\ a \times - 2 + b = 27 \\ - 2a + b = 27 \\ \\ a \times 5 + b = - 8 \\ 5a + b = - 8 \\ \\ - 2a + b = 27 \\\:\:\:\: 5a+ b = - 8 [/tex]
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[tex] - 7a = 35 \\ a = \frac{35}{ - 7} \\ a = - 5[/tex]

[tex]- 2a + b = 27 \\ - 2 \times - 5 + b = 27 \\ 10 + b = 27 \\ b = 27 - 10 \\ b = 17 \\ \\ a + b \\ = - 5 + 17 \\ = 12[/tex]