Answer: [tex]11x-8y=-9[/tex]
Step-by-step explanation:
For this exercise you need to remember:
1) The mulitplication of signs:
[tex](+)(+)=+\\(-)(-)=+\\(-)(+)=-\\(+)(-)=-[/tex]
2) By definition, like terms contain the same variables with the same exponent.
Then knowing this, and given the equations:
[tex]8x - 4y = -4[/tex] and [tex]-3x+ 4y = 5[/tex]
You must subtract the like terms, which means that you must subtract the numerical coefficients of each term.
Then, you get the result is:
[tex]8x - 4y = -4\\-3x+ 4y = 5\\...............................................\\8x-(-3x)-4y-4y=-4-5\\8x+3x-8y=-9\\11x-8y=-9[/tex]