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Which is an equation of the line thruogh (-1,-4) and parallel to the line 3x+y=5

User Mattsven
by
4.0k points

2 Answers

2 votes

Answer:

y = -3x - 7

Explanation:

3x + y = 5

y = -3x + 5

Parallel lines have the same slope, so m = -3

y - -4 = -3(x - -1)

y + 4 = -3(x + 1)

y + 4 = -3x - 3

y = -3x - 7

User Serigne
by
2.9k points
5 votes

Answer:

y = -3x-7

Explanation:

3x+y=5

First put this in slope intercept form

Subtract 3x from each side

3x-3x+y=-3x+5

y = -3x+5

The slope is -3 and the y intercept is 5

Parallel lines have the same slope so our new line will have a slope of -3

It goes through the point (-1,-4)

Using slope intercept form

u = mx+b

y = -3x+b

Substituting the point into the equation to solve for b

-4 = -3(-1) +b

-4 = 3+b

-4-3 = b

b = -7

Using the slope and the y intercept

The line is y = -3x-7

User Ihab
by
3.6k points