A = -18r +13 - 2x -14
= -18r +13 -14 - 2x
= -18r -1 -2x
B= y +25 - 12y2 +7y - 15 + 20y2
= y +25 - 24y + 7y -15+ 40y
= y-24y+7y+40y +25 -15
= 24y +25 -15
= 24y + 10
C= 5x+7+(-12x-8)
= 5x+7-12x-8
= 5x -12x +7-8
= -7x -1
D= (5x - 12) + (8x + 15)
= 5x-13+8x+15
= 5x+8x-13+15
= 1
E= 8x × 2x + 5x
= 16x² +5x
F=7x × x - 2x
= 7x² - 2x
