Can some me with algebra 2 work? its problems 45-48 all and 53-57 just odd numbers

45)

E = mc²     (solve for "m" by dividing both sides by c²)

E/c² = m

46)

c(a + b) - d = f  (to solve for "a"; add "d", divide by "c" and then subtract "b")

c(a + b)     = f + d

(a + b)       = (f + d)/c

a              = (f + d)/c  - b

47)

z = πq³h   (solve for "h" by dividing both sides by πq³)

z/πq³ = h

48)

(x + y)/z - a = b   (solve for "y"; add "a", multiply by "z", and then subtract "x")

(x + y)/z      = b + a

(x + y)         = z(b + a)

     y           = z(b + a) - x

53)

5x - 9 = 11x + 3

     -9 = 6x + 3      subtracted 5x from both sides

    -12 = 6x          subtracted 3 from both sides

      -2 = x           divided both sides by 6

55)

5.4(3k - 12)   +   3.2(2k + 6) = -136

16.2k - 64.8   +  6.4k + 19.2 = -136      distributed 5.4 and 3.2

22.6k - 45.6 = -136             added like terms (16.2k + 6.4k and -64.8 + 19.2

22.6k = -90.4                    added 45.6 to both sides

      k = -4                       divided both sides by 22.6

57)

(4/9)y + 5 = (-7/9)y - 8

4y + 45 = -7y - 72           multiplied by 9 to clear the denominator

11y + 45 = -72                 added 7y to both sides

11y         = -99                  subtracted 45 from both sides

y            = -9                    divided both sides by 11