Explain a strategy you could use to check the answer to a division problem. write you explanation

When using the linear combination metho e linear combination method to solve a system of linear equations, the four options are:

Which statement explains how you could use coordinate geometry to prove the opposite sides of a quadrilateral are congruent? a. use the slope formula to prove the slopes of the opposite sides are the same. b. use the slope formula to prove the slopes of the opposite sides are opposite reciprocals. c. use the distance formula to prove the lengths of the opposite sides are the same. d. use the distance formula to prove the midpoints of the opposite sides are the same.

Suppose the equation ||x-a|-b|=2008 has 3 distinct real roots and a not =0. find the value of b.