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Solving "Ax + By = C" for "y=" (page 2 of 2) Sections: Solving for a given variable, Solving for "y=" Probably one of the more important classes of literal equations you will need to solve will be linear equations. For instance, it is common that you are given problems of this type:
In order to find the slope, it is simplest to put this line equation into slopeintercept form. If I rearrange this line to be in the form "y = mx + b", it will be easy to read off the slope m. So I'll solve: 3x
+ 2y = 8
Then the slope is m = ^{–3}/_{2} . Warning: There are many contexts, such as graphing and systems of equations, in which you will need to be able to solve a linear equation for "y =", so make sure you are comfortable with these techniques.
I'll solve for "y =": Copyright © Elizabeth Stapel 20022011 All Rights Reserved
2x
– y = 5
Then y = 2x – 5, and, from the slopeintercept form of y = mx + b, I can see that: the slope is m = 2 and the yintercept is b = –5.
I'll solve for "y =": x
– 2y = 5
Then y = ( ^{1}/_{2} ) x – ( ^{5}/_{2} ), so: the slope is m = ^{1}/_{2} and the yintercept is b = ^{–5}/_{2} .
I'll solve for "y =": 4x
+ 5y = 12
Then the slope is m = ^{–4}/_{5} and the yintercept is b = ^{12}/_{5} . Don't let literal equations "throw" you. Solving literal equations is just like solving linear (and other sorts of) equations, except that the answers don't simplify as much. The techniques involved are otherwise exactly the same. Just take your time and be sure to write out all your steps clearly. << Previous Top  1  2  Return to Index



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