SOLUTION: Given: 2x + 3y = 12 2x - y = 4 What is the value of x + y? A -5 B -1 C 1 D 5

Algebra ->  Expressions-with-variables -> SOLUTION: Given: 2x + 3y = 12 2x - y = 4 What is the value of x + y? A -5 B -1 C 1 D 5      Log On


   

Question 393186: Given:

2x + 3y = 12
2x - y = 4

What is the value of x + y?

A -5
B -1
C 1
D 5
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

2x + 3y = 12

2x - y = 4 

SOLVING: first for y by elimination (subtracting 2nd equation from 1st)

2x + 3y = 12

-2x + y = -4 

     4y = 8   y = 2

2x - y = 4

  2x -2 = 4

     2x = 6   x = 3

 x + y = 5



Note: it is typical for certain types of testing to take solving

for x and y which is what is usually done by various methods.... to another level 

and ask for the answer in terms of the sum as is done in this example.