what is the sum of this equation(5x+2y=7)+(3x-y=2)

Answer 1

5x + 2y = 7

3x - y = 2

8x +y = 9

add like terms.

(5x+3x) = 8x

(2y-y) = y

7+ 2 = 9

(5x+3x) +(2y-y) = 7+2

8x + y = 9

usually though, you'd add equations in order to eliminate one variable.

to do that you need to multiply the 2nd equation by 2 before adding the equations

5x+2y = 7

3x-y = 2

6x-2y = 4, then add them

5x+2y = 7

11x = 11

x = 11/11 = 1

y = 3x-2 = 3-2 = 1

x = 1, y = 1 is the solution