Answer:
Use the general point-slope formula
+%28+y+-+%28-7%29+%29+%2F+%28+x+-+%28-8%29+%29+=+5%2F4+
+%28+y+%2B+7+%29+%2F+%28+x+%2B+8+%29+=+5%2F4+
+4%2A%28+y+%2B+7+%29+=+5%2A%28+x+%2B+8+%29+
+4y+%2B+28+=+5x+%2B+40+
+4y+=+5x+%2B+12+
+y+=+%285%2F4%29%2Ax+%2B+3+
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check:
does it go through ( -8, -7 )?
+-7+=+%285%2F4%29%2A%28-8%29+%2B+3+
+-7+=+-10+%2B+3+
+-7+=+-7+