Вопрос школьника по предмету Математика
Мы проходим тему «Упрощение выражений» и я её не много не поняла, объясните пожалуйста на этих примерах надо раскрыть скобки
2x-(2x+y)+y
-a+(2a-b)+2b
-(7-x)+(3x-14)
-(x+4)-(2x-8)
2(3-x)-(8+x)
-4(y+5)+(12-y)
1/2*(x+4/5)-(1/5-x)
-2/3*(6/7-y)+(2/7+y)
7/8*(4-x)-(3/4+x)
-(3/19-y)-1/2(y+2/19)
Ответ учителя по предмету Математика
раскрываешь скобки и приводишь подобные
2x-(2x+y)+y=2х-2х-у+у=0
-a+(2a-b)+2b=-а+2а-в+2в=а+в
-(7-x)+(3x-14)=-7+х+3х-14=-21+4х
-(x+4)-(2x-8)=-х-4-2х+8=-3х+4
2(3-x)-(8+x)=6-2х-8-х=-2-3х
-4(y+5)+(12-y)=-4у-20+12-у=-5у-8
1/2*(x+4/5)-(1/5-x)=1/2х+2/5-1/5+х=1 1/2х+1/5
-2/3*(6/7-y)+(2/7+y)=-4/7+2/3у+2/7+у=-2/7+1 2/3у
7/8*(4-x)-(3/4+x)=3 1/2-7/8х-3/4-х=2 3/4-1 7/8х
-(3/19-y)-1/2(y+2/19)=-3/19+у-1/2у-1/19=-4/19+1/2у
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