Question

Simplifique as expressões

C)(x-3).(x.5)+3x(x+4)

D)-6x(x+y)+(x-y).(2x+3y)

E)(a+b).(a-b)+(a-2b).(a+5b)

F)(x+1).(x+2)-(x-4).(x-5)

Answer 1

c) (x - 3),(x - 5) + 3x(x + 4) = x² - 8x + 15 + 3x² + 12x = 4x² +4x + 15
d) -6x(x + y) + (x - y),(2x + 3y) = -6x² -6xy + 2x² + xy - 3y² = -4x² - 5xy - 3y²
e) (a + b).(a - b) + (a - 2b),(a + 5b) = a² - b² + a² +3ab - 10b² = 2a²-11b²+3ab
f) (x+1).(x+2) - (x-4).(x-5) = x² + 3x + 2 - (x² - 9x + 20) = 12x - 18