Question 503418
y = mx + b
.
m = (change in y) / (change in x)
change in y = 8-2 = 6
change in x = 5-2 = 3
m = 6/3
m = 2
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y = 2x + b
.
Substitute (2,2)
2 = 4 + b
b = -2
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y  = 2x -2
.
Check with the other point
2x -2 = ?
2(5) -2 = 10-2
10-2 = 8
Correct.
.
{{{graph(500,500,-10,10,-10,10,2*x-2)}}}