Ace, genius, trusted ! if x = 2a − b^2 , which expression represents a? show your ! i already know the answer, i just need with the work. i am crying right now because no one is answering my questions correctly. people are putting wrong answers or are putting right answers without work. it really isn't nice. a. x + b^2 b. (b^2 - x)/2 c. (x + b^2)/2 d. (x - b^2)/2 show ! i beg of you!

Selection C is appropriate.


Whenever you solve for something, consider what operations are done to that something. Undo them in reverse order.

Here, "a" is
• multiplied by 2
• has -b^2 added

The last operation is adding -b^2, so we undo that first. We undo it by adding its opposite, b^2.
.. x +b^2 = 2a -b^2 +b^2
.. x +b^2 = 2a . . . . . . . . . . . the point is to cancel the -b^2 term on the right.

The operation before that is multiplying "a" by "2". We undo that by multiplying by the reciprocal of 2, which is 1/2.
.. (1/2)*(x +b^2) = (1/2)*2a
.. (x +b^2)/2 = a . . . . . . . . . the point is to cancel the multiplication by 2 on the right.

You will note this matches answer selection C.