Answer:
Prime.
Step-by-step explanation:

First let's multiply our outer coefficients in this case 1 and 8, so we have 1x8=8. Now the point of this is to get the factors of 8 and see if we can get that middle term -7. Factors of 8 are 1x8, 2x4 and that's it. From there I notice that -8+1 = -7 and so:

Notice that the (x-8) and (x+8) are not the same factors, therefore the factors are not any of those answer choices and so it's prime. You can calculate the factors by using the quadratic formula, however I think that is beyond the scope of this question.
Remember that

So if
and
, then we know
.
Then use the Pythagorean identity to solve for cosine:

Answer:
<em>x is 12 and y is 3</em>
Step-by-step explanation:
Given a parallelogram LMNO,
LM = ON and OL = NM
Given;
ON = 9x - 8
LM = 8x + 4
NM = x - 8, and
OL = 3y - 5
Substitute into the expression
LM = ON
8x + 4 = 9x - 8
8x - 9x = -8 - 4
-x = -12
x = 12
Also OL = NM
3y - 5 = x - 8
3y - 5 = 12-8
3y - 5 = 4
3y = 4+5
3y = 9
y = 9/3
y = 3
<em>Hence the value of x is 12 and y is 3</em>
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A and b are not true because