# Another simple math problem (y=mx+b)

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Write an equation in slope-intercept form for each line described.

(I just need my work checked, thank you!)

The slope = 1/2, and the line passes through the point (3, -1)

First I used point slope formula
y-ysub1 = m(x-xsub1)
y+1=1/2(x-3)
then, went on to distribute, getting
y+1 = 1/2x - 1 1/2
Then subtract 1 on both sides,
getting y = 1/2x - 1/2

Is this correct? Thank you very much in advance.

• Another simple math problem (y=mx+b) - ,

Wait, I think I found my problem... I had added y+1 rather than subtracted.

• Another simple math problem (y=mx+b) - ,

NEVERMIND again, I was right, hence the y - -1 would have been addition.. sorry guys! Still need someone to check for me! :) lol

• Another simple math problem (y=mx+b) - ,

y = 0.5x - 2.5

Slope = 1 / 2 = 0.5

For x = 3

y = 0.5x - 2.5 = 0.5 * 3 -2.5 = 1.5 - 2.5 = -1

• Another simple math problem (y=mx+b) - ,

from your
y+1=1/2(x-3)
y+1 = (1/2)x - 3/2
y = (1/2)x - 5/2 or y = (1/2)x - 2 1/2