Question

Rút gọn biểu thức:

a) (-37) – (x + 23) + 15 =

b) 176 – (176 - x + 42) =

c) 1270 – (1270 – 2x) + 31 =

d) 2x + (-141) – (231 – 461) =

Answer 1

Lời giải:

a.

$=-37-x-23+15=-x-(37+23)+15=-x-60+15=-x-(60-15)=-x-45$

b.

$=176-176+x-42=0+x-42=x-42$

c.

$=1270-1270+2x+31=0+2x+31=2x+31$

d.

$=2x-141-231+461=2x-(141+231)+461=2x-372+461$

$=2x+(461-372)=2x+89$