Question

If 3x + 2y = 10 and 2x + 3y = 15, find the value
of x+y.​

Answer 1

x+y=5

Explanation:

Isolate y in the first equation:

3x+ 2y = 10

2y = 10 - 3x

y= (10 - 3x)/2

substitute this value of y into the second equation:

2x + 3 ((10 - 3x)/2) = 15

now solve for x:

2x + 3/2 (10 - 3x) =15

2x + 15 - 9/2x = 15

-5/2 x = 15 - 15

-5/2 x / (-5/2) = 0/(-5/2)

x=0

now use this value to solve for y:

y = (10 - 3(0))/2

y = 10/2

y = 5

now x+y

0+5=5