Sagot :
Bonsoir,
A=5(9y - 4)
45y-20
B = (8x + 1)(4x - 5)
32x²-40x+4x-5
32x²-36x-5
C = (2a + 7)(5a - 10) - 8(3a + 4)
10a²-20a+35a-70-24a-32
10a²-9a-102
D = (7 - 2x)(5 - 8x) - (3 - 20x²)
35-56x-10x+16x²-3+20x²
36x²-66+32
E = (2y + 4)(5y - 1) + (3y + 7)(y-2)
10y²-2y+20y-4+3y²-6y+7y-14
13y²+19y-18
F = 7(2x² - 7x + 4) + (x + 1)(x + 2)
14x²-49x+28+x²+2x+x+2
15x²-46x+30
G = 5(2 + 4x²) - 7(3 - 8x) + (2x + 1)(6x - 9)
10+20x²-21+56x+12x²-18x+6x-9
32x²+44x-20
a= 5(9y - 4) = 45y - 20
b= (8x + 1) (4x- 5) = 32 x² - 40 x + 4x -5 = 32x² -36x -5
c = (2a + 7) (5 a-10) - 8 (3a + 4) = 10a² -20 a + 35 a - 70 - 24 a -32
= 10 a² - 11 a - 102
d= (7 - 2x)(5-8x) - (3-20x²)= 35 -56x -10x+16 x²- 3 -20x² = - 4x²-66x + 32
e = (2y+4)(5y-1)+(3y+7)(y-2)
= (10y²-2y+20y -5 ) + (3y² -6 y +7 y-14)
= 13 y² + 19 y -19
f= 7(2x²-7x+4)+(x+1)(x+2)
= 14x²-49x+28 + x²+2x +x +2
= 15 x²- 46 x + 30
g= 5(2+4x²)-7(3-8x)+(2x+1)(6x-9)
= 10 +20x² -21 + 56x + 12x²- 18 x + 6x -9
= 32 x² + 44 x - 48