Hi There!
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Find The Slope:

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Find The Y-Intercept:
Substitute using x = 2 and y = 8
Use y = mx + b
Substitute: 8 = 2.5(2) + b
Simplify: 8 = 5 + b
Subtract 5 too both sides: 8 - 5 = 5 + b - 5
Simplify: 3 = b
Y-Intercept = 3
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Point Slope Form: y - 8 = 2.5(x - 2)
Slope Intercept Form: y = 2.5x + 3
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Hope This Helps :)