math

how would you solve for x? can you explain step by step?
40 = [(x+2.8)/2]*8.5

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asked by Andrea
  1. 40 = [(x+2.8)/2]*8.5
    multiply both sides by 2 to remove the 2 in the denominator.
    40*2 = 2*[(x+2.8)/2]*8.5
    80 = (x+2.8)*8.5
    remove parentheses on right side by multiplying by 8.5.
    80 = 8.5x + 2.8*8.5
    80 = 8.5x + 23.8
    move 23.8 to left side.
    80-23.8 = 8.5 x
    combine terms on left.
    56.2 = 8.5x
    divide both sides by 8.5
    56.2/8.5 = 8.5x/8.5
    6.61176 = x
    Check my work.
    Check it also by substituting the value of x into the original equation and see if the right side = 40.

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    posted by DrBob222

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