- - = + 9-(-4)= 9+4 so minus minus becomes plus. and 13 is the answer.
Hello,
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Y=x-4
x=y+4
y=-3(y+4)
y=-3y-12
4y=-12
y=-3
x=1
Answer:
10 + 5xy = -80
Step-by-step explanation:
10 + 5xy = ?
x = 9 and y = -2
10 + 5xy = 10 + 5(9)(-2)
= 10 - 90
= -80