Đáp án:
Bạn tham khảo nhé!
Giải thích các bước giải:
`1`
`a)``3/5+(-2)/5=(3-2)/5=1/5`
`b)``(-11)/7*3/17+4/17*3/17`
`=3/17((-11)/7+4/7)`
`=3/17*(-1)`
`=(-3)/17`
`c)``2^3-8.3+0,5.25%`
`=8(1-3)+1/2*1/4`
`=8(-2)+1/8`
`=-16+1/8`
`=(-127)/8`
`d)``3 1/2+0,8+3/5`
`=3 1/2+4/5+3/5`
`=3 1/2+7/5`
`=7/2+7/5`
`=49/10`
`2`
`a)``2/7x=(-1)/6`
`(2x)/7=(-1)/6`
`2x=(7(-1))/6`
`2x=(-7)/6`
`x=(-7)/12`
`b)``2/3.(x+1)+3/4=7/12`
`(2(x+1))/3+3/4=7/12`
`(2x+2)/3+3/4=7/12`
`(4(2x+2))/12+9/12=7/12`
`4(2x+2)+9=7`
`4(2x+2)=-2`
`8x+8=-2`
`8x=-10`
`x=(-10)/8`
`x=(-5)/4`
`c)``|x+2|=5`
\(\left[ \begin{array}{l}x+2=5\\x+2=-5\end{array} \right.\) `=>`\(\left[ \begin{array}{l}x=3\\x=-7\end{array} \right.\)
