Question

What is an equation of the line thatpasses through the point (-1,-3) and is parallel to the line 4x-y=2?

Answer 1

Step-by-step explanation:

First, you put the equation into the standard “slope/intercept” form.

4x -y = 2 subtract 4x from both sides ; -y = -4x + 2 Multiply by -1 :

y = 4x - 2

In this standard form we see that the slope of the line (coefficient of x) is 4. ANY line parallel to this one must thus also have a slope of 4.

y = 4x - a (generic)

ANY other combination of slope multiples and constant terms will therefore also be lines parallel to this one. The one that passes through a specific point will simply have a different constant term.

We find this by putting our point value into the equation:

3 = 4(-2) + a ; 3 = -8 + a ; a = 11

Thus, our “parallel line equation” through the point (-2,3) is:

y = 4x + 11

Answer 2

y = 4x + 1

Step-by-step explanation:

first put the equation 4x-y=2 into the form y = mx + b where m is the slope and b is the y-intercept (for example, y = 2x - 1 would have 2 is the slope and -1 is the y-intercept)

4x - y = 2

subtract 4x from both sides

-y = -4x + 2

multiply both sides by -1

y = 4x - 2

That means the slope of this line is 4.

Parallel lines always have the same slope, so the slope of the new line is also 4. You can again put the new equation into the form y = mx + b. You already know that the slope is 4, so y = 4x + b.

Next, you need to find b. You know that (-1, -3) is a solution, so if you plug x = -1 and y = -3 into the equation, it should be true.

You can put that into the equation to solve for b:

-3 = 4 * -1 + b

-3 = -4 + b

1 = b

This means the equation is y = 4x + 1