It’s answer C. You multiply 8 & 13, which will give you 104. Then, multiply 8 & 2y, which will also give you 16y.
5y= -6x+2
5y/5 =-6x/5 +2/5
y = -1.2x +0.4
the slope is -1.2 and y intercept is 0.4
Using substitution:
first you have to express one variable in terms of the other, in this we can express y in terms of x:

Since both expressions are equal to y, you have to equal both expressions like this:

Now you can solve the equation:

Knowing x=10, you can use any of the expressions we found before to find y. In this case I'm going to use y= -x+9 because it's simpler but boy should give you the same result

So, the answer is x=10 and y=-1
The sum can be rewritten as y=4x, where y=f(x).
Now, we can rewrite the equation a x=y/4
Therefore, inv(f(x))=x/4
The answer is:
(v-1)(v+1)(v^2+1)