SOLUTION: Good Afternoon, I would really appreciate any help possible to turn this equation below that was done in a substitution technique into GRAPHICAL Technique. y=4x-7 3x+2y=30

Algebra ->  Equations -> SOLUTION: Good Afternoon, I would really appreciate any help possible to turn this equation below that was done in a substitution technique into GRAPHICAL Technique. y=4x-7 3x+2y=30       Log On


   

Question 804134: Good Afternoon, I would really appreciate any help possible to turn this equation below that was done in a substitution technique into GRAPHICAL Technique.
y=4x-7
3x+2y=30
Take the second equation:
3x+2y=30
Replace the letter "y" by the right side of the first equation which is
4x-7 placed within parentheses like this: (4x-7)
3x+2(4x-7)=30
Now use the distributive principle
to remove the parentheses.
3x+8x-14=30
Combine the like terms 3x and 8x
and get 11x
11x-14=30
Add 14 to both sides
11x=44
Divide both sides by 11
x=4
That's the answer for x,
But you also need the value for y.
So take the first equation
y=4x-7
And replace x by (4)
y=4(4)-7
y=16-7
y=9
So the solution is: x=4 and y=9
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Your system of two equations:
y=4x-7
3x+2y=30

Solve both equations for y, and graph each line on the same coordinate system.
The second equation, 2y=-3x%2B30
y=-%283%2F2%29x%2B30%2F2
y=-%283%2F2%29x%2B15 Slope Intercept form.
The first equation is already solved for y and is in slope intercept form.

y-intercept for the first equation is read from the equation, at y=-7.
y-intercept for the second equation is +15=y.
You would use the slope to count where other reference points are found.

THIS graph helps you see how to plot the lines.
graph%28500%2C500%2C-10%2C15%2C-10%2C16%2C4x-7%2C-%283%2F2%29x%2B15%29

This graph lets you see the intersection of the lines more closely:
graph%28500%2C500%2C-1%2C10%2C-1%2C12%2C4x-7%2C-%283%2F2%29x%2B15%29
Notice the intersection appears to be (4,9).