`a, 11/13 - (5/42 - x) = - (15/28 - 11/13)`
`⇔5/42-x = 113/364+11/13`
`⇔x = 5/42-421/364`
`⇔x = -1133/1092`
`b, x + 1/3 = 2/5 - ( -1/3)`
`⇔x = 11/15-1/3`
`⇔x = 2/5`
`c, - 5/8 - x = - 3/20 - (-1/6)`
`⇔x = -5/8-1/60`
`⇔x = -77/120`
`d, x - (-1/4) = -5/6+1/8`
`⇔x = -17/24+(-1/4)`
`⇔x = -23/4`
`e, -2/3 x = 4/15`
`⇔x = 4/15÷(-2/3)`
`⇔x = -2/5`
`g, x ÷22/15 = -8/27`
`⇔x = -8/27 . 22/15`
`⇔x = -176/405`
Xin hay nhất !