Answer:
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Answer: THIRD OPTION.
Step-by-step explanation:
We need to remember that we can create a perfect square trinomial by squaring a binomial:

Then we need need to pick the coefficient of the x term of the given expression, divide it by 2 and square it:

Therefore, the number that should be added to the given expression in order to create a perfect square trinomial is:
The third one is the answer
I believe the answer would be 17,250. Hope this helps!
First, expand the brackets on the left hand side.
You have: 8x-6=4x-78
Minus least number of x first on each side, so minus 4x
2x-6=-78
Then add 6 to both sides
2x= -72
Then divide both sides by 2 to get x on its own
X= -36
(-72/2=-36)