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Write an equation of the line that passes through (1,2) and is parallel to the line y=−5x+4

y=?

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User Neitsa
by
7.3k points

2 Answers

7 votes

You are using the equation:

y = mx + b

You need to find "m" and "b".

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

For the equation of the line to be parallel to the given equation, the slopes have to be the SAME. The slope of the given line is -5, so the parallel line's slope is also -5. (m = -5)

y = mx + b

y = -5x + b

To find b, you plug in the point (1,2) into the equation

y = -5x + b

2 = -5(1) + b

2 = -5 + b Add 5 on both sides to get "b" by itself

2 + 5 = -5 + b + 5

7 = b


Your equation is:

y = -5x + 7

User Mikiko
by
7.8k points
3 votes

We know that the slope is -5, so:

y = -5x + b

Input (1, 2)

2 = -5 + b

b = 7

So:

y = -5x + 7

User NSUser
by
7.4k points