Solving a linear equation

Fred solved the equation 8(3x - 7) = -6(x + 7) + 4 as shown.

Given          8(3x - 7) = -6(x + 7) + 4
Step 1         24x - 56 = -6x - 42 + 4
Step 2         24x - 56 = -6x + 46
Step 3         30x = 102
Step 4         x = 17/5

Fred made an error between step 1 and step 2.
a.)  Explain the error that Fred made.
b.)  What is the solution of the original equation?

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8(3x - 7) = -6(x + 7) + 4   Given
24x - 56 = -6x - 42 + 4
24x - 56 = -6x - 38   ← Fred took -42 + 4 to be 46 instead of the correct -38, shown here
+6x  +56    +6x  +56
30x = 18   {added 6x and added 56 to each side}
x = -18/30   {divided each side by 30}
x = -3/5   {reduced}

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