Question

5)Reduza os termos semelhantes de cada polinômio:
a) 8 a + 5 b - 2 a – 7b +12 a

b) 6x² + 6x² - 4x +4x +15

c)4x² - 6x – 2 - x² +x +2

d) 18c+6d+10c-24d

e)2( x+y) + 4( x – y) +12+6

ME AJUDEM PFVR, TENHO QUE ENTREGAR ATE AS 9 HORAS.

Answer 1

a) 8 a + 5 b - 2 a – 7b +12 a

$8a+5b-2a-7b+12a=18a-2b\\8a+5b-2a-7b+12a\\8a-2a+12a+5b-7b\\8a-2a+12a=18a\\18a+5b-7b\\\:5b-7b=-2b\\18a-2b\\16$

b) 6x² + 6x² - 4x +4x +15

$a+5b-2a-7b+12a=18a-2b\\8a+5b-2a-7b+12a\\8a-2a+12a+5b-7b\\8a-2a+12a=18a\\18a+5b-7b\\\:5b-7b=-2b\\18a-2b\\16$

c)4x² - 6x – 2 - x² +x +2

$4x^2-6x-2-x^2+x+2=3x^2-5x\\4x^2-6x-2-x^2+x+2\\4x^2-x^2-6x+x-2+2\\4x^2-x^2=3x^2\\3x^2-6x+x-2+2\\-6x+x=-5x\\3x^2-5x-2+2\\-2+2=0\\3x^2-5x\\x=3²-5x\\x=4$

d) 18c+6d+10c-24d

$18c+6d+10c-24d=28c-18d\\18c+6d+10c-24d\\18c+10c+6d-24d\\18c+10c=28c\\28c+6d-24d\\6d-24d=-18d\\28c-18d\\10$

e)2( x+y) + 4( x – y) +12+6

$2\left(x+y\right)+4\left(x-y\right)+12+6=6x+18-2y\\2\left(x+y\right)+4\left(x-y\right)+12+6\\2\left(x+y\right):\quad 2x+2y\\2x+2y+4\left(x-y\right)+12+\\4\left(x-y\right):\quad 4x-4y\\6x+18-2y\\+108-2y\\y=106\\ou\\\\2x+2y+4x-4y+12+6:\quad 6x+18-2y\\2x+2y+4x-4y+12+6\\2x+4x+2y-4y+12+6\\6x+2y-4y+12+6\\6x-2y+12+6\\6x+18-2y\\+108-2y\\y=106$