Question

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

Answer 1

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

Answer 2

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).