SOLUTION: Find the equation of a line through the point (-1,9) and parallel to 2x-4y=7.

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Question 509400: Find the equation of a line through the point (-1,9) and parallel to 2x-4y=7.
Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
A line parallel to 2x-4y = 7 will have the same slope.
2x-4y = 7
-4y = -2x +7
y = (-2/-4)x + (7/-4)
y = 1/2x - 7/4
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Slope = 1/2
so the sought equation will have slope = 1/2.
.
y = 1/2x + b
.
We want it go through the point (-1,9),
so we use that point to define 'b'.
.
9 = 1/2(-1) + b
9 = -1/2 + b
b = 9 + 1/2
b = 18/2 + 1/2
.
y = 1/2x + 19/2
.
In the following graph, the first equation is in red, the second is in green.
.
graph%28500%2C500%2C-20%2C20%2C-20%2C20%2C1%2F2%2Ax-7%2F4%2C+1%2F2%2Ax%2B19%2F2%29