Question

Solve the following system of equations.

Answer 1

Answer:

(2,-3)

Step-by-step explanation:

I am not sure if you meant the first equation to be y or -y.  I solved it as y.

y = x-5                       -x -3y =7

I am going to take the second equation and write it as x =

-x - 3y = 7  Give equation

-x = 3y +7   Add 3y to both sides

x = -3y-7  Multiplied each term in the equation by -1 so that x could be positive

I am going to substitute -3y-7 for x in the first equation up above

y = x - 5

y = -3y -7 - 5  Substitute -3y-7 for x

y = -3y -12  Combined -7-5

4y = -12  Added 3y to both sides

y = -3  Divided both sides by 4.

I now know that y is -3, I will plug that into x = -3y-7 to solve for x

x = -3(-3) -7

x = 9-7   A negative times a negative is a positive

x = 2