Question

Find the equation of a line through the point (-1,4)and parallel to the line whose equation is 2x-y=3

Answer 1

Slope-intercept form:

y = mx + b

"m" is the slope, "b" is the y-intercept (the y value when x = 0 or (0,y))

You can first isolate the "y" in the given equation

2x - y = 3    Subtract 2x on both sides

-y = 3 - 2x     Divide -1 on both sides to get "y" by itself

y = -3 + 2x  or   y = 2x - 3

For lines to be parallel, their slopes have to be the same.

The given line's slope is 2, so the parallel line's slope is also 2.

y= mx + b

y = 2x + b

To find "b", plug in the point (-1,4) into the equation

y = 2x + b

4 = 2(-1) + b

4 = -2 + b     Add 2 on both sides

6 = b

y = 2x + 6