34. a) 2/x = 4/5
: 2 = (4/5)x
: 2*(5/4) = x
: x = 10/4 = 5/2 = 2.5
b) 12/(-7) = 3/x
: (12/(-7))x = 3
: x = 3*((-7)/12)
: x = -21/12 = -1.75
35. a) (x+2)/6 = -5
: x+2 = -30
: x = -32
b) -8 = 12/(2x-3)
: -8(2x-3) = 12
: -16x+24 = 12
: -16x = -12
: x = 12/16 = 3/4 = 0.25
36. (x+3)/4 = (5-2x)/3
: (3(x+3))/4 = 5-2x
: (3x+9)/4 = 5-2x
: 3x+9 = 4(5-2x)
: 3x+9 = 20-8x
: 11x = 11
: x = 1
37. (3-8x)/(-5) = (-1+7x)/4
: (4(3-8x)/(-5) = -1+7x
: (12-32x)/(-5) = -1+7x
: 12-32x = (-5)(-1+7x)
: 12-32x = 5-35x
: -3x = 7
: x = -(7/3)