How do you solve for M in $-0.50=(47-M)/(56-M)$ ?

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Answer 1 · 2017-01-10T22:15:30

$M = 50$

First, multiply each side of the equation by $color(red)(56 - M)$ to eliminate the fraction:

$-0.50 xx (color(red)(56 - M)) = (47 - M)/(56 - M) xx (color(red)(56 - M))$

$-28 + (0.50 xx- M) = (47 - M)/color(red)(cancel(color(black)((56 - M)))) xx cancel((color(red)(56 - M)))$

$-28 + (0.50M) = 47 - M$

$-28 + (0.50M) + color(blue)(28) + color(red)(M) = 47 - M + color(blue)(28) + color(red)(M)$

$-28 + color(blue)(28) + (0.50M) + color(red)(M) = 47 + color(blue)(28) - M + color(red)(M)$

$0 + 1.50M = 75 - 0$

$1.50M = 75$

$(1.50M)/color(red)(1.50) = 75/color(red)(1.50)$

$(color(red)(cancel(color(black)(1.50)))M)/cancel(color(red)(1.50)) = 50$

$M = 50$

How do you solve for M in -0.50=(47-M)/(56-M)-0.50=(47-M)/(56-M)?