去括号 2(a-b)-3(c+d) -5/2(m-n)+1/3(c+d) 去括号并合并同类项: (8x-5y)-(4x-9y)

问题描述:

去括号 2(a-b)-3(c+d) -5/2(m-n)+1/3(c+d) 去括号并合并同类项: (8x-5y)-(4x-9y)
去括号并合并同类项: x-(2x-y)+(3x-2y) 2(x+y)+(-5x+2y) -2(-3xy+2z)+3(-2xy-5x)

2(a-b)-3(c+d)
=2a-2b-3c-3d

-5/2(m-n)+1/3(c+d)
=-5/2m-5/2n+1/3c+1/3d

(8x-5y)-(4x-9y)
=8x-5y-4x+9y
=4x+4y


x-(2x-y)+(3x-2y)
=x-2x+y+3x-2y
=2x-y

2(x+y)+(-5x+2y)
=2x+2y-5x+2y
=-3x+4y

-2(-3xy+2z)+3(-2xy-5x)
=6xy-4z-6xy+15x
=15x-4z