How do you solve this system of equations: #7x + y = 11;- 10x - 5y = 20#?
The method I am using is subsitution.
First, isolate x in the second equation as it is easier to do so;
Then, replace x in the first equation with the equation above;
Now we know y equals to -10
Now, substitute this value to y of the second equation
And x equals to 3