Question

Which of the following points is a solution to the system of equations x - y = 1 and -x + 3y = - 7?

Answer 1

Answer:

(-2,-3)

Step-by-step explanation:

Put the equations over each other.

$\binom{x - y = 1}{ - x + 3y = - 7 }$

Subtract the x values.

$\binom{ - y = 1}{3y = - 7}$

Subtract on both sides.

$2y = - 6$

Divide on both sides.

$y = - 3$

Insert the y value into one of the equations.

$x - ( - 3) = 1$

Get rid of the parenthesis.

$x + 3 = 1$

Subtract on both sides.

$x = - 2$

You could also individually plug in each solution into both equations to see if they are true.