5x − 15 = −2
+15 +15 add 15 to both sides, 15's will cancel out and solve -2 + 15.
__________
5x 13 <--- sum of -2 + 15
__ = __ divide 5 on both sides, 5's will cancel out on the left side.
5 5
x = 2.6, final answer :)
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