Question

What two numbers have a sum of -7 and a difference of 14?

Answer 1

The first number, x, is 3.5. The other number, y, is 10.5.
X+y=-7
X-y=14.
Those are the two equations. If you use the elimination method, and add those two equations together, the resulting equation is 2x=7. That means the first variable is 3.5. So, 3.5-y=-7, so that means y is -10.5. If you plug that in with the other equation then it comes out as true.

Answer 2

The sum of two numbers is 14 and their difference is 10

Explanation:

"2 numbers (x and y)

x+y = 14

and x-y + 10

If you each equation by positive 2, one gets 2x+2y = 28 and 2x-2y = 20

The 'y-terms' cancel out or equal zero when adding, so 4x = 48, divide by 4 on each side and x or the first number equals 12.

Plug 12 back into the equation for 'x' and subtract 12 on both sides so that y=2

The difference of 12-2=10 and the addition of 12 and 2 equals 14"

hopes this helps