...sub those values into the equation. So x= -10 and y=2.5 so 2.5=3(-10)+b....3 remains the slope as a results of fact the line is parallel, so clean up that equation for b =32.5. So your equation is y=3x+32.5

Lines are parallel so the slopes are equal.

Thus the slope of the required line is 3

by the equatin y = mx + c

m --> The slope!

so

(y - 7) / (x - 3) = 3

Solving we get 3x - y = 2

=)

y=3x-2