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25 votes
25 votes
Solve the following system of equations by graphing.
-4x + 3y = - 12
- 2r + 3y = - 18

User Joginder S Nahil
by
2.8k points

1 Answer

13 votes
13 votes
I believe the answer is (-3,-8)

When using the graphing method, you can use a “hide and divide approach”

So for the first equation, you would hide the -4 (by multiplying it by zero) and then figure out what, multiplied by 3, gets -12. Then do the opposite for the other number.

That comes out as (0,-4) for one point, and (3,0) for the other. [-4•3=-12 and 3•-4=-12]

You would then follow the same process for the next equation.

You would get (0, -6) and (9,0). [3•-6=-18 and -2•9=-18].

Then you graph the lines, connecting the points you found, they should extent beyond the points on both sides.

From there, you find the intersection point and that would be your solution, which in this case is (-3,-8)

To check if your solution is correct, plug in the numbers in the correct place.

-4 (-3) + 3 (-8) = -12
12 + -24 = -12
-12 = -12

-2 (-3) + 3(-8) = -18
6 + -24 =-18
-18 = -18

Please correct me if I am wrong
Solve the following system of equations by graphing. -4x + 3y = - 12 - 2r + 3y = - 18-example-1
User RoadRash
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2.6k points