SOLUTION: find the point (x,y) which satisfies both equations. What is the value of x + y? -2x + 4y = 12 3x - 5y = -3

Algebra ->  Square-cubic-other-roots -> SOLUTION: find the point (x,y) which satisfies both equations. What is the value of x + y? -2x + 4y = 12 3x - 5y = -3      Log On


   

Question 443236: find the point (x,y) which satisfies both equations. What is the value of
x + y?
-2x + 4y = 12
3x - 5y = -3
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
find the point (x,y) which satisfies both equations.
:
-2x + 4y = 12
3x - 5y = -3
:
We can use elimination here, multiply the 1s eq by 3, the 2nd eq by 2, results:
-6x + 12y = 36
+6x - 10y = -6
------------------addition eliminates x fin y
0 + 2y = 30
y = 30%2F2
y = 15
:
Use the 1st equation to find x, replace y with 15
-2x + 4(15) = 12
-2x + 60 = 12
-2x = 12 - 60
-2x = -48
x = %28-48%29%2F%28-2%29
x = +24
:
The x,y point that satisfies, 24,15
:
What is the value of x + y?
24 + 15 = 39
:
:
Check solution in the original 2nd equation
3x - 5y = -3
3(24) - 5(15) = -3
72 - 75 = -3