8.4 should be your answer
bearing in mind that an absolute value expression is in effect a piece-wise expression, since it has a positive and a negative sibling.

Step-by-step explanation:
5x+8-3x=-10
2x+8= -10
2x=-10-8
2x=-18
therefore x= -9
<span>perpendicular slope :
m1 * m2 = -1
1/2 * m2 = -1
m2 = -2
y = -2x + b
2 = -4 +b
b = 6
y = -2x + 6
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