The first step I would take is
.. Multiply both sides of the equation by 1/4.
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You could start by adding 16 to both sides of the equation, to make the left side the square (2x +4)^2.
Factor the expression:
-1/6*6(x-2y)
Divide by 6
-1(x-2y)
Then times by -1
-x+2y
Is your answer
Hope this helps
4 ........................................
The answer is 2,100. since there are 3 feet in 1 yard, you would multiple 700 by 3.