calculer x=-8/3 A=(3x-7)au carré+(2x+5)(7-3x)

A=(3*(-8/3)-7)²+(2*(-8/3)+5)(7-3*(-8/3))

A=(-8-7)²+(-16/3+5)(7+8)

A=(-15²)+(-16/3+15/3)(15)

A=225+(-1/3)*15

A=225-5=220

A = (3x - 7)² + (2x + 5) (7 - 3x)

A = 9x² - 42x + 49 + 14x - 6x² + 35 - 15x

A = 9x² - 6x² - 42x - 15x + 14x + 49 + 35

A = 3x² - 43x + 84

A = 3 * (- 8/3)² - 43 * (- 8/3) + 84

A = 3 * (64/9) + 344/3 + 84

A = 192/9 + 1032/9 + 756/9

A = 1980/9

A = 220