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Write an equation of a line through the point (2,-1) and parallel to -2x+4y=8

User Sherece
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1 Answer

4 votes

Answer:

y = 1/2x - 2

Explanation:

If an equation is paralell to another equation, that means the slopes are the same. To find the slope of -2x + 4y = 8, we must simplify and rearrange it.

-2x + 4y = 8

Add 2x on both sides

4y = 2x + 8

divide by 4 on both sides to isolate y

y = 1/2x + 2

Using this information, we know that the slope of the equation is 1/2.

So far, our equation is this:

y = 1/2x + b

We don't know what the y-intercept is, but we know that it intersects a point (2, -1). We can plug in the x and y values to find out what the b intercept is.

y = -1, x = 2

-1 = 1/2(2) + b

Simplify

-1 = 1 + b

Subtract 1 on both sides

-2 = b

The y-intercept is -2, so we can plug this back into our original equation.

Final answer: y = 1/2x - 2

User Pelle Jacobs
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