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Question from chris:

find the slope and y intercept of the line (2x+4)-3y=11(x-1)
is this equation in slope point form.

Hi Chris,

The point slope form of a line is

y - y1 = m(x - x1)

where m is the slope and (x1, y1) is the point. Your equation is not in this form.

I'm going to look at a different equation 4x + 5 - (2y + 4) = 3(x - 5) with the same instructions, find the slope and y intercept. Since it is the slope and y intercept that you want I am going to put the equation in slope intercept form, y = mx + b. In this form m is the slope and b is the y intercept.

I would first remove the parentheses and simplify each side

4x + 5 - (2y + 4) = 3(x - 5)
4x + 5 - 2y - 4 = 3x - 15
4x - 2y + 1 = 3x - 15

The slope intercept has y on the left of the equal sign and everything else on the right. I have the y term on the left but also 4x + 1 so to move 4x + 1 to the right I subtract 4x + 1 from each side and simplify

4x - 2y + 1 - (4x + 1) = 3x - 15 - (4x + 1)
-2y = 3x - 15 - 4x - 1
-2y = -x - 16

Finally divide both sides by -2 to get

y = 1/2 x + 8

The equation is now in slope intercept form and I can now see that the slope is 1/2 and the y intercept is 8.

Now try your equation,
Penny

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