how do you solve the system -x-6y=13 and -x+y=-1

2 answers

We can use substitution method to solve the system of equations. We begin by solving one of the equations for one of the variables.

From the second equation, we have:

-x + y = -1

which means:

y = x - 1

Now we can substitute this expression for y into the first equation:

-x - 6y = 13

to get:

-x - 6(x - 1) = 13

Simplifying this, we get:

-7x + 6 = 13

-7x = 7

x = -1

Now that we have found x, we can use the equation y = x - 1 (which we obtained earlier) to find y:

y = -1 - 1 = -2

So the solution to the system of equations is (x,y) = (-1,-2).
I would just subtract them:
-7y = 14
y = -2
now sub back into -x+y=-1
-x -2 = -1
x = -1

x = -1, y = -2