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What is an equation of the line that passes through the point (- 7, 0) and is parallel to the line x + y = 1

User Xaxazak
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1 Answer

9 votes

Answer:

y = -x - 7

Explanation:

If two lines are parallel to each other, they have the same slope.

The first line is x + y = 1.

First, let's put this into standard form.

x + y = 1

y = -x + 1

Now we have an equation in standard form. Its slope is -1. A line parallel to this one will also have a slope of -1.

Plug this value (-1) into your standard point-slope equation of y = mx + b.

y = -x + b

To find b, we want to plug in a value that we know is on this line: in this case, it is (-7, 0). Plug in the x and y values into the x and y of the standard equation.

0 = -1(-7) + b

To find b, multiply the slope and the input of x (-7)

0 = 7 + b

Now, subtract 7 from both sides to isolate b.

-7 = b

Plug this into your standard equation.

y = -x - 7

This equation is parallel to your given equation (y = -x + 1) and contains point (-7, 0)

Hope this helps!

User Tintu C Raju
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4.4k points