I would use the process of elimination. Divide 13 from both sides
2x+7y=-57 y=-7 then plug in y to an equation
-6x-8y=80 2x+7(-7)=-57 multiple
multiple the first equation by 3 2x-49=-57 add 49 to both sides
6x+21y=-171 2x=-8 divide two from both sides
-6x-8y=80 x=-4
combine like terms So your things would be x=-4 and y=-7
13y=-91 And itd make the solution (-4,-7).
The answer will still be 2/3 because you * it by 1
Question is not written properly but i think you are looking for the table of given equation y=400-55x. So I will explain about how to get that.
number of hours can't be negative so that means x must be 0 or more.
like x=0,1,2,3,...
we just have to plug these x-values into above equation to find the y-value in order to calculate table.
I will show you calculation for x=2
y=400-55x=400-55*2=400-110=290
so the point in table will be (2,290)
similarly we can find more point and get final table as shown below:
Division and multiplication