SOLUTION: How do you solve this problem? please show work. Solve by graphing y=2x+3 x+y=3

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Question 63647: How do you solve this problem? please show work.
Solve by graphing y=2x+3
x+y=3

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by graphing
E1: y=2x+3
E2: x+y=3
:
For E1:
(I'm graphing this line by plotting points.)
Let x=0 and solve for y:
y=2(0)+3
y=0+3
y=3 Plot (0,3)
Now let x=2 and solve for y (Pick any point within reason.)
y=2(2)+3
y=4+3
y=7 Plot (2,7)
Connect the points and you should have this line:
graph%28300%2C200%2C-10%2C10%2C-10%2C10%2C2x%2B3%29
For E2:
(I'm graphing this line by the intercept method.)
Let x=0 and solve for y:
0+y=3
y=3 Plot (0,3)
Notice that both lines have the same y-intercept. This is the solution to the system. (We're not supposed to know that yet, and most of the time we won't, so let's keep graphing.)
Let y=0 and solve for x:
x+0=3
x=3 Plot (3,0)
Connect the points and you have a second line:
graph%28300%2C200%2C-10%2C10%2C-10%2C10%2C2x%2B3%2C-x%2B3%29
The lines intersect at the solution: (0,3)
Happy Calculating!!!!