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kel214
Dec 24, 2006, 12:11 PM
I need to solve for y. How do I go about finding the answer to this problem. 2y+5x=7

Fianchetto
Dec 24, 2006, 06:32 PM
I need to solve for y. How do I go about finding the answer to this problem. 2y+5x=7

The result will have the form : y=mx+b

or, more specifically, 1y+0 =mx+b

The rule is that since it's an equality, the same operations must be performed Both sides of the "=".

Figure out how to make the +5x=0 and do it to both sides.
Figure out how to make the 2=1 and do that to both sides.


I hope I'm not too ambiguous, but reply and I'll try to show you the general case.

Fianchetto:)

galactus
Dec 25, 2006, 04:25 PM
2y+5x=7

Subtract 5x from both sides:

2y=7-5x

Divide by 2:

y=\frac{7-5x}{2}

Now, in slope-intercept form:

y=\frac{-5}{2}x+\frac{7}{2}

7/2 is where it crosses the y-axis and 5/2 is the slope.