if r + t = s and r - t = -s which of the following must be equal to t? (A) 5, (B) 15, (C) 20, (D) 45, (E) 80

Solve 3x-18=2y and 5x-6y=6 by elimination show work

Elena is paid a constant rate for each hour she works. the table shows the amounts of money that elena earned for various amounts of time that she worked.

Which equation shows the variable terms isolated on one side and the constant terms isolated on the other side for the equation -1/2x+3=4-1/4x? a. -1/4x=1 b. -3/4x=1 c. 7=1/4x d. 7=3/4x