Answer:

Explanation:
5 = −⅘[10] + b
−8

If you want it in Standard Form:
y = −⅘x + 13
+ ⅘x + ⅘x
___________
⅘x + y = 13 [We do not want fractions in our standard equation, so multiply by the denominator to get rid of it.]
5[⅘x + y = 13]

* Perpendicular Lines have OPPOSITE MULTIPLICATIVE INVERSE RATE OF CHANGES [SLOPES], so 1¼ [or 5⁄4] becomes −⅘.
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