What should be added to 2x + 8y to get 8x - 9y ?
10x – y
6x – y
6x – 17y
6x + 17y
Here sum is 8x – 9y . So we have to take away 2x + 8y from this.
(8x – 9y) – ( 2x + 8y) = 8x – 9y – 2x – 8y
= 8x – 2x -9y -8y
= 6x – 17y