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How do you solve #m/8=(m+7)/9#?

Answer 1

Abigail Allen

#m=56#

#"one way is to use "color(blue)"cross-multiplication"#

#•color(white)(x)a/b=c/drArrad=bc#

#rArr9m=8(m+7)larrcolor(blue)"distribute"#

#rArr9m=8m+56#

#"subtract "8m" from both sides"#

#9m-8m=cancel(8m)cancel(-8m)+56#

#rArrm=56#

#color(blue)"As a check"#

This value is the solution if you substitute it into the equation and both sides come out equal.

#"left "=56/8=7#

#"right "=(56+7)/9=63/9=7#

#rArrm=56" is the solution"#

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Answer 2

Eli Assouline

To solve the equation ( \frac{m}{8} = \frac{m+7}{9} ), you would first cross multiply to eliminate the denominators. Then, solve for ( m ). The steps are:

Multiply both sides by ( 8 ) to eliminate the denominator in the first fraction: ( 8 \cdot \frac{m}{8} = 8 \cdot \frac{m+7}{9} ).
Simplify both sides: ( m = \frac{8(m+7)}{9} ).
Multiply both sides by ( 9 ) to eliminate the denominator in the second fraction: ( 9m = 8(m+7) ).
Distribute ( 8 ) on the right side: ( 9m = 8m + 56 ).
Subtract ( 8m ) from both sides: ( m = 56 ).

The solution is ( m = 56 ).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.