+0  
 
0
41
2
avatar+12 

solve the problem using substitution.

x-2y=-2

3x-2y=2

cesix  Oct 25, 2017

Best Answer 

 #1
avatar+5229 
+2

This is a little bit different from the normal way of substituting, but it is still substution!

 

x - 2y  =  -2

3x - 2y  =  2

 

(x - 2y) - (3x - 2y)  =  (x - 2y) - (3x - 2y)

                                                              Since  x - 2y = -2 , we can substitute  -2  in for  x - 2y .

(x - 2y) - (3x - 2y)  =  (-2) - (3x - 2y)

                                                              Since  3x - 2y = 2 , we can substitute  2  in for  3x - 2y .

(x - 2y) - (3x - 2y)  =  (-2) - (2)

                                                   Distribute the  -1 .

x - 2y - 3x + 2y  =  -2 - 2

                                                   Combine like terms.

-2x  =  -4

                                                   Divide both sides by  -2 .

x  =  2

 

Now we know what  x  is. Let's plug this value into the first equation to find  y .

 

2 - 2y  =  -2

                      Subtract  2  from both sides.

-2y  =  -4

                      Divide both sides by  -2 .

y  =  2

hectictar  Oct 25, 2017
Sort: 

2+0 Answers

 #1
avatar+5229 
+2
Best Answer

This is a little bit different from the normal way of substituting, but it is still substution!

 

x - 2y  =  -2

3x - 2y  =  2

 

(x - 2y) - (3x - 2y)  =  (x - 2y) - (3x - 2y)

                                                              Since  x - 2y = -2 , we can substitute  -2  in for  x - 2y .

(x - 2y) - (3x - 2y)  =  (-2) - (3x - 2y)

                                                              Since  3x - 2y = 2 , we can substitute  2  in for  3x - 2y .

(x - 2y) - (3x - 2y)  =  (-2) - (2)

                                                   Distribute the  -1 .

x - 2y - 3x + 2y  =  -2 - 2

                                                   Combine like terms.

-2x  =  -4

                                                   Divide both sides by  -2 .

x  =  2

 

Now we know what  x  is. Let's plug this value into the first equation to find  y .

 

2 - 2y  =  -2

                      Subtract  2  from both sides.

-2y  =  -4

                      Divide both sides by  -2 .

y  =  2

hectictar  Oct 25, 2017
 #2
avatar+12 
0

solve the systems of equations:

 

3x+y=20
2x+3y=18     (no graph)

cesix  Oct 25, 2017

21 Online Users

avatar
avatar
avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details