MHB Rearranging the subject of an equation help please

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To rearrange the equation abc/3 = c^2 + a(b + 2) to make b the subject, start by expanding the brackets and isolating terms with b. After expansion, the equation simplifies to abc/3 = c^2 + ab + 2a. Next, collect all terms containing b on one side, resulting in abc/3 - ab = c^2 + 2a. Clearing the fraction by multiplying through by 3 is a suggested next step to simplify further. Understanding these steps can help overcome algebraic challenges.
sarannie
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Please please can you help me understand how to rearrange this formula to make b the subject:
abc/3=c^2+a(b+2)
 
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Start by expanding the brackets, moving every term that has a "b" to one side, and taking b out as a factor.
 
Prove It said:
Start by expanding the brackets, moving every term that has a "b" to one side, and taking b out as a factor.

Thank you, I have an absolute mental block with algebra.
So do I do a x b a x 2 next?
 
sarannie said:
Thank you, I have an absolute mental block with algebra.
So do I do a x b a x 2 next?

Hi there,

Yep, I think I know what you mean and if so that's the right idea. After expanding you'll get this:

$$\frac{abc}{3}=c^2+ab+2a$$

Now what you should do is collect the terms with a "$b$" in them on one side and terms without on the other. If you do that you'll get this:

$$\frac{abc}{3}-ab=c^2+2a$$

With me so far? Any idea what to do next?
 
You are very good to help me, thank you.
I'm wondering about clearing that fraction by multiplying by 3?
 
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