153k views
4 votes
Which is an equation of the line that is parallel to y = 2x - 8 and passes through the point (0, - 3) ?

User Fang Zhang
by
5.0k points

2 Answers

1 vote
Parallel means same slope. Keep the 2x. New equation is y=2x + b. b is the y-intercept. Now plug in the point you got from the equation and solve for b
User PSN
by
4.8k points
3 votes

Answer:

y=2x-3

Explanation:

1. The condition that the line is parallel tells you the slope: it will be the same in parallel lines. You now have an equatipn of the new line:

y=mx+b, in which m is slope, which you know:

y=2x+b

2. (0,-3) is a coordinate (x,y), so plug these in for x and y in your equation to solve for b, the y-intercept

-3=2(0)+b Anything multiplied by zero is zero

-3=0+b

-3=b

3. Rewrite the new equation with your known m and b values

y=2x-3

*NOTE* In this specific problem, there was a shortcut: since (0,-3) is on the y-axis, you know that it is the y-intercept, and the y-value of that point is b, so you could have gotten -3 without any calculations

User Ryan Crews
by
4.8k points