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Which equation represents a line that is parallel to the line represented by

4x + y = 7 and passes through the point (1, 8)?

User Tamjid
by
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1 Answer

2 votes

Answer:

y = -4x + 12

Explanation:

For a line to be parallel, it needs to have the same slope.

Point intercept form: y - y₁ = m (x - x₁)

Where y and x are just kept as y and x, y₁ and x₁ are the parts of a coordinate, and m = slope.

So, in order for the line to be parallel, it needs to have the same slope as the first equation. The slope of the line (which is the "m" in y = mx + b) is..

4x + y = 7

y = -4x + 7

So, m, or the slope, is -4.

Plug this, along with the coordinate the problem gives you into point-intercept form.

y - y₁ = m (x - x₁)

y - 8 = -4 (x - 1)

Simplify.

y - 8 = -4x + 4

Add 8 to both sides.

y = -4x + 12

User Jozef Izso
by
2.9k points