Question

Write an equation for the line that is parellel to the given line and that passes through the given point?

y = 2x + 7; (3, 11)

a.y = 2x – 19

b.y=1/2x+5

c.y= -1/2x-5

d.y = 2x + 5

Answer 1

y = 2x + 5 (answer d)

Explanation:

Parallel lines have the same slope, and thus, if we're given y = 2x + 7, we know that the slope of the 'new' line is 2. This 'new line' passes through (3, 11). Begin with the point-slope formula y - k = m(x - h) and substitute 3 for h, 11 for k and 2 for m:

y - 11 = 2(x - 3)

Rewriting this in slope-intercept form, we get:

y = 2x - 6 + 11. or y = 2x + 5 (answer d)