one number is 3 times another number and their sum is -16

y is one number
x is the other number.
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x + y = -16
3x = y
solve for x and y.
Post your work if you need further assistance.

To solve the given system of equations, let's start by rearranging the first equation:

x + y = -16

Subtracting y from both sides, we get:

x = -16 - y

Now we can substitute this expression for x into the second equation:

3x = y

Substituting -16 - y for x, we have:

3(-16 - y) = y

Expanding and simplifying:

-48 - 3y = y

Now, let's solve for y:

-48 = 4y

Dividing both sides by 4:

-12 = y

So, we have found the value of y. Now, let's substitute this value back into one of the original equations to solve for x:

x + (-12) = -16

x - 12 = -16

Adding 12 to both sides:

x = -16 + 12

x = -4

Therefore, the solution to the system of equations is x = -4 and y = -12.