5X plus 5y equals -7 how do you solve by elimination?

Answer 1

To solve for two unknowns (x and y) you need two independent equations.

All that you can do with the above is to express x in terms of y, as follows:

5x + 5y = -7

x + y = -7/5

x = -7/5 -y

Similarly, you could express y in terms of x as: y = -7/5 -x

IF, you had a value for either x or y from some other equation (or other source), you could substitute that value in either of these equations to solve for the other.