kak minta tolong yaaa.pake cara :)

15.) 4x - 8y + 3 = 15
-8y= -4x - 3 + 15
y = -4x + 12
= -4x + 12
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-8
= 1/2x - 1 1/2
( jawaban = c. 1/2 )

16). rumusnya = y - y¹ = y² - y¹
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x² - x¹