Using the process of elimination how do you solve 4x + 8y = 20 -4x + 2y = -30

Question

How do i solve the process of elimnation?

Answer 1

PROBLEM: 4x + 8y = 20

                     -4x + 2y = -30

 

Answer:

4x and -4x get canceled &, so now you have

 

8y = 20

2y = -30

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10y = -10      <==== ADD the y's & solve for Y

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10      10

 

y = -1

 

 

Choose any of the two given equations n the problem(I chose equation #1) & solve for X!

 

4x + 8y = 20   <=== ORIONAL EQUATION

4x + 8 (-1) = 20 <=== Substitution

4x -8 = 20

     +8    +8   <=== Add 8

4x = 28 <== Solve for X

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4      4

 

X = 7

 

 

(7, -1)