SOLUTION: how can i graph a line with 3x+4y=12? help please! thanks in advance

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Question 270145: how can i graph a line with 3x+4y=12? help please! thanks in advance
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
your equation is:

3x+4y=12

you have to solve for y to get:

y = (12-3x)/4

now you can graph the equation.

your graph looks like this:

graph%28600%2C600%2C-5%2C5%2C-5%2C5%2C%2812-3x%29%2F4%29

note that the slope intercept form of a linear equation is y = mx + b where m is the slope and b is the y intercept.

I just solved for y.

I can make that equation into the slope intercept form very easily though.

I gave you the equation of :

y = (12-3x)/4

I divide this equation out to get:

y = (12/4) - (3x/4)

I simplify to get:

y = 3 - (3/4)*x

I rearrange the terms on the right side of the equation to get:

y = -(3/4)*x + 3

The slope is -(3/4) and the y intercept is 3

If you look at the graph, you will see that when x = 0, y = 3. That's your y-intercept point.

You will also see that when x move 4 units in the positive direction (from x = 0 to x = 4), y move 3 units in the negative direction (from y = 3 to y = 0).

That's your slope (-3/4) which is the change in y divided by the change in x