`a) 17 -x = 80 - (-7)`
` => 17 - x = 80 +7`
` => 17 - x = 87`
`=> -x = 87-17`
`=> -x = 70`
`=> x= -70`
`b) x-28 = (-32)-8`
`=> x - 28 = -40`
`=> x = -40 + 28`
`=> x = -12`
`c) x/6 = 5/(-10)`
`=> -10x = 5.6`
`=> -10x =30`
`=> x = 30 :(-10)`
`=> x = -3`
`d) 4/x = (-2)/7`
`=> -2x = 4.7`
`=> -2x = 28`
`=> x = 28 : (-2)`
`=> x = -14`
`e) 5/8 : x = 7/10`
`=> x = 5/8 : 7/10`
`=> x = 25/28`
`f) x + 2/17 = 9/17`
`=> x = 9/17 - 2/17`
`=> x = 7/17`
`g) 1/12 + x = 3/8`
`=> x = 3/8 - 1/12`
`=> x = 7/24`