Write the series using summation notation.

This is so harddd! solve. 1 + 1 = solve 4 + 4 = solve 3 x 3

Quadrilateral wxyz is on a coordinate plane. segment yz is on the line x+y=7 and segment xw is on the line x+y=3. which statement proves how segments yz and xw are related

Which of the following points is a solution to the system of equations shown? y - x = -1 x + y = -5