1% = $4
$4 × 100 = $400
$4 × 18 = $72
Your answer is $400
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Answer:

Step-by-step explanation:
hope this helps!
2x-4y=-16
ax+4y=6 +
--------------------
2x+ax=-10; for x=-2,
2(-2)+a(-2)=-10
-2a=-10+4
a=-6/-2
a=3