A little help

I could be wrong, but this is what I got...

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specialj96 said:
Problem is 2/A - 3/Y = 1/B solve for Y

Matt is "almost" correct.

2/A - 3/Y = 1/B

3/Y = 2/A - 1/B

3/Y = (2*B - A)/(A*B) ... one assumption ... (2B-A)<>0

Y/3 = A*B/(2*B - A)

Y = 3*A*B/(2*B - A)
 
Ah, you are correct Subhotosh Khan. My mistake! I worked it out again to be sure.

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Matt, go stand in the corner (which Subhotosh just vacated).
 
Hello, specialj96!

\(\displaystyle \frac{2}{A} - \frac{3}{Y} \:=\:\frac{1}{B} \qquad\text{ Solve for }Y.\)

Evidently, no one hates fractions as much as I do.
I always eliminate them immediately if possible.

\(\displaystyle \text{We have: }\;\frac{2}{A} - \frac{3}{Y} \:=\:\frac{1}{B}\)

\(\displaystyle \text{Multiply through by }ABY:\;\;\rlap{\:/}ABY\left(\frac{2}{\rlap{\:/}A}\right) - AB\rlap{/}Y\left(\frac{3}{\rlap{/}Y}\right) \:=\:A\rlap{\:/}BY\left(\frac{1}{\rlap{\:/}B}\right)\)

. . . . . . . . . .\(\displaystyle \text{and we have: }\qquad 2BY\quad -\quad 3AB \qquad=\qquad AY\)


\(\displaystyle \text{Re-arrange terms: }\;2BY - AY \;=\;3AB\)


. . . . . . . \(\displaystyle \text{Factor: }\;(2B - A)Y \;=\;3AB\)

\(\displaystyle \text{Therefore: }\;Y \;=\;\frac{3AB}{2B-A}\)

 
soroban said:
Hello, specialj96!

\(\displaystyle \frac{2}{A} - \frac{3}{Y} \:=\:\frac{1}{B} \qquad\text{ Solve for }Y.\)

Evidently, no one hates fractions as much as I do. ... Denis does .... ask him (he is the one sitting in the corner for being "wise guy" - trying send Matt to the corner...)
I always eliminate them immediately if possible.

\(\displaystyle \text{We have: }\;\frac{2}{A} - \frac{3}{Y} \:=\:\frac{1}{B}\)

\(\displaystyle \text{Multiply through by }ABY:\;\;\rlap{\:/}ABY\left(\frac{2}{\rlap{\:/}A}\right) - AB\rlap{/}Y\left(\frac{3}{\rlap{/}Y}\right) \:=\:A\rlap{\:/}BY\left(\frac{1}{\rlap{\:/}B}\right)\)

. . . . . . . . . .\(\displaystyle \text{and we have: }\qquad 2BY\quad -\quad 3AB \qquad=\qquad AY\)


\(\displaystyle \text{Re-arrange terms: }\;2BY - AY \;=\;3AB\)


. . . . . . . \(\displaystyle \text{Factor: }\;(2B - A)Y \;=\;3AB\)

\(\displaystyle \text{Therefore: }\;Y \;=\;\frac{3AB}{2B-A}\)

 
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