Question 99774
Solve the following for the variable "b". Please note that the variables are "a" and "A" are different and unique variables. 
{{{A}}} = {{{1/2}}}{{{h(a + b)}}} 
This is what I came up with am I on the right track?? 
A = ½ ha + ½ hb
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That was OK but not this:
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<s>A- ½ ha / ½ h = ½ hb / ½ h</s>
<s>A – a = b</s>
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{{{A}}} = {{{1/2}}}{{{h(a + b)}}}

{{{A}}} = {{{1/2}}}{{{ha}}} + {{{1/2}}}{{{hb}}}

Next, clear of fractions by multiplying every
term on both sides by LCD = {{{2}}}:

{{{2}}}·{{{A}}} = {{{2}}}·{{{1/2}}}{{{ha}}} + {{{2}}}·{{{1/2}}}{{{hb}}}

{{{2A}}} = {{{ha}}} + {{{hb}}}

Get the only term containing {{{b}}} alone on the right by
subtracting {{{ha}}} from both sides:

{{{2A -ha}}} = {{{hb}}}

Divide both sides by the coefficient of {{{b}}}, which is {{{h}}}:

{{{(2A -ha)/h}}} = {{{(hb)/h}}}

Cancel only the {{{h}}}'s on the right:

{{{(2A -ha)/h}}} = {{{b}}}

That is the answer.  Do not cancel the h's
on the left side because h is not a factor
of the numerator but only a factor of one term
of the numerator.

Answer:

{{{b}}} = {{{(2A -ha)/h}}}

Edwin</pre>