Question

Find (r-s) (t-s) + (s-r) (s-t) for all numbers r, s, and t.
(a) 0
(b) 2
(c) 2rt
(d) 2(s-r) (t-s)
(e) 2(r-s) (t-s)

Answer 1

Multiply them out and you get 2RT-2ST-2RS+2S^2 Remove the 2 getting:
2(RT-ST-RS+S^2) Factoring what is in the parentheses gives:
2(R-S)(T-S)

Answer 2

thank you so much (y)

Answer 3

You're welcome.