Given points P(-2,7) and Q(4,y) in a coordinate plane, for what value of y is the slope of the line through P and Q equal to 2/3?
y2 – y1
m = –––––––
x2 – x1
2 y2 – 7
–– = –––––––
3 4 – (–2)
crossmultiply
(3)(y2 – 7) = (2)(4 + 2)
3y2 – 21 = 8 + 4
3y2 = 33
y2 = 11
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