I need help "Solving Linear Systems by Graphing"

3x + y=10
Y= 2x - 5

If you graph each of those equations, the intersection will be the solution. Start by picking a value of X; solve for Y and graph that point. Continue by selecting new values of X

Not too crazy over Perito's answer, but it works. All you need is two points because it's a slope intercept kind of equation.

If you put the equations into the form Y=mX+b, you can find Y when X=0 and you also know the slope from m, so you have a line for each equation.

The intersection of the line is the solution.

Actually,I'd do the problem both ways so you understand both techniques.

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Not too crazy over Perito's answer, but it works.

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I'm not too crazy about the answer either, except the petitioner asked about solving "by graphing," so I gave the appropriate answer.

pick a value of X; solve for Y and graph that point

Both methods are graphing but one might be easier depending on the problem. Recognizing that they are lines and only 2 points or a slope and intercept are required for each equation are necessary is also important. Pick points that are easy to calculate.

Yes, I too would have opted for a two point plotting, then drawing the line. Now, those points should be as far as possible to minimise errors.