Solving Very Hard Algebra: Step by Step Guide

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To solve the algebraic expressions ax/b + cx/d = e and a/bx + c/d = e for x, a step-by-step breakdown is necessary. For the first equation, using the distributive property and finding a common factor is crucial, leading to the solution x = edb/(ad + bc). The second equation requires careful manipulation to isolate x, resulting in x = da/b(ed - c). It's important to maintain accuracy in each step, as incorrect multiplication or rearrangement can lead to errors. Understanding these principles will aid in successfully making x the subject in both expressions.
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Well it's very hard for me anyway!
In both of the following expressions I have to make x the subject. Can anybody break them down for me and explain step by step how to solve them?

1.
ax/b + cx/d = e

2.
a/bx + c/d = e

From looking at the answers I know that the solutions are as follows:
1. x = edb/ad+bc
2. x = da/b(ed-c)
 
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Gringo123 said:
Well it's very hard for me anyway!
In both of the following expressions I have to make x the subject. Can anybody break them down for me and explain step by step how to solve them?

1.
ax/b + cx/d = e

2.
a/bx + c/d = e

From looking at the answers I know that the solutions are as follows:
1. x = edb/ad+bc
2. x = da/b(ed-c)

I can give you a hint.

For 1. start by using the distributive property
 
So that would mean...
- ax/b + cx/d = e
- axd+cxb/bd = e
and from there I can get to the answer x = edb/ad+bc by using and rearranging the formula A=BC/D. Is that the right way to do it?

I've have tried applying the same logic to number and it doesn't seem to work.

Thanks for your help by the way.
 
Gringo123 said:
So that would mean...
- ax/b + cx/d = e
- axd+cxb/bd = e
and from there I can get to the answer x = edb/ad+bc by using and rearranging the formula A=BC/D. Is that the right way to do it?

No; the above steps are incorrect. You've taken the term cx/d and multiplied top and bottom by b, which makes no difference to that term; but you've replaced ax/b with axd.

The distributive property, in this case, means you should look for a common factor. This is a good way to approach problem number 1. The original equation is
ax/b + cx/d = e

Can you see any common factors there?

Cheers -- sylas

PS. Your solution to number 1 needs some parentheses.
 
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