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2x -( y+2)/2 = 22

3x + (y+2)/3 = 7

Solve the set by substitution method

 May 27, 2015

Best Answer 

 #2
avatar+250 
+15

It'd be easier to multiply the first equation by 3 and the second by 2 then subtract the 2nd equation from the 1st to get one equation in terms of y, but since you said it had to be the substitution method here goes:

2xy+22=222x=22+y+22x=11+y+24

Now Substituting x into the other Equation:

3[11+y+24]+y+23=799+9(y+2)4+y+2=21396+9y+18+4y+8=8413y=338y=26x=11+26+24x=5

 May 27, 2015
 #1
avatar+33654 
+15

Rearrange the first equation to get x = (y+2)/4 + 11

 

Put this into the second equation

3*(y+2)/4 + 3*11 + (y+2)/3 = 7

 

Multiply through by 4*3

9*(y+2) +12*3*11 + 4*(y+2) = 12*7

So

9y + 18 + 396 + 4y + 8 = 84

13y + 422 = 84

13y = -338

y = -26

 

Put this back into the first equation above

x = (-26+2)/4 + 11

x = 5

 

You should check these by putting them back into the original equations.

.

 May 27, 2015
 #2
avatar+250 
+15
Best Answer

It'd be easier to multiply the first equation by 3 and the second by 2 then subtract the 2nd equation from the 1st to get one equation in terms of y, but since you said it had to be the substitution method here goes:

2xy+22=222x=22+y+22x=11+y+24

Now Substituting x into the other Equation:

3[11+y+24]+y+23=799+9(y+2)4+y+2=21396+9y+18+4y+8=8413y=338y=26x=11+26+24x=5

Brodudedoodebrodude May 27, 2015

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