# Algebra

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i am having problems understanding.... i don't know how to put it so i will just put what the problem is

Write the slope-intercept form of an equation of the line that passes through the given point and is parallel to the graph of each equation
13. (2,-7) y= x-2

i know that 2 and -7 is the slope to the line that i have to get the new line to be parallel to it.... if that makes sence... but please help!!!

• Algebra - ,

in the y-intercept slope form
y = mx + b
the slope is m and the y-intercept is b

(2, -7) is a point and tells you nothing about the slope.

so the given line is y = x-2
or y = 1x - 2, so you know the slope must be 1, since the two lines are to be parallel

and the new line must look like
y = 1x + b, where only the y-intercept or the b would have changed
Now we plug in our new point (2,-7)
-7 = 1(2) + b
b = -9

your new equation parallel to the old one is

y = x - 9

• Algebra - ,

ohhhhhh now i see ok can i do one and could you tell me if im right??

• Algebra - ,

will be here for another 15 minutes

• Algebra - ,

(2,-1) y=2x+2
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y=2x+b
-1=2(2)+b
-1=4+-5
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y=2x-5 <--- is this right?

• Algebra - ,

yep. to check, just plug in (2,-1) and see whether it satisfies the equation. Since 2(2)-5 = -1, you're right on.

• Algebra - ,

thank you sooooo much!!!!