Have I rearraged this formula correctly?

  • Thread starter Gringo123
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It should look like this:m = (5t + 7)/3In summary, to make m the subject of the given equation, you need to follow these steps: move the 3 to the left side, move the -t to the left side, divide both sides by 2, and simplify the resulting expression. The final equation for m is (5t + 7)/3.
  • #1
Gringo123
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I have to make m the subject:

3(2m - t) = 2t + 7

This is my attempt:

m = (0.5t + 3.5 / 1.5) + 0.5t
 
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  • #2
Gringo123 said:
I have to make m the subject:

3(2m - t) = 2t + 7

This is my attempt:

m = (0.5t + 3.5 / 1.5) + 0.5t

Could you please show each step?
 
  • #3
sure
3(2m - t) = 2t + 7
move the 3 to the left side

2m - t = 2t + 7 / 3

move the -t to the left side
2m = (2t + 7 /3) +t

divide both sides by 2
m = (t + 3.5 / 1.5) +0.5t

and I realize this is slightly different to the 1st solution that I put up. 2t / 2 is of course t, not 0.5t.

Anyway, is it right?
 
  • #4
No, it's not right. When you divide 7/3 by 2 you should get 7/6, not 3.5/1.5, which is equal to 7/3.

BTW, You really ought to learn which is left and which is right...

Also, in your second equation, the right side should have parentheses:
2m - t = (2t + 7)/3

In the following line you added parenthese, but they are not where you need them. This equation should be written like so:
2m = (2t + 7)/3 +t

Finally, the expression you have for m, besides being incorrect, should be written more simply, with the t terms combined.
 

FAQ: Have I rearraged this formula correctly?

How can I tell if I have rearranged a formula correctly?

To ensure that you have correctly rearranged a formula, you can follow these steps:

  1. Check that all variables and constants are present in both the original and rearranged formula.
  2. Make sure the units on each side of the equation are the same.
  3. Solve the original and rearranged equation for a few different values of the variables and compare the results.
  4. Double check your work by plugging the rearranged equation back into the original equation and simplifying.
If all of these steps check out, then you have most likely rearranged the formula correctly.

What are some common mistakes when rearranging formulas?

Some common mistakes when rearranging formulas include:

  • Forgetting to apply the distributive property.
  • Mixing up signs (+/-) when moving terms from one side of the equation to the other.
  • Not performing the same operation to both sides of the equation.
  • Forgetting to flip the sign when dividing or multiplying by a negative number.
Be sure to double check your work and be mindful of these common errors.

Can I rearrange a formula with multiple variables?

Yes, you can rearrange a formula with multiple variables. The key is to isolate the variable you are solving for on one side of the equation and keep the other variables on the other side. You may need to use multiple steps and algebraic principles, such as the distributive property, to rearrange the formula correctly.

Is there a specific order or steps to follow when rearranging formulas?

There is no specific order that you must follow when rearranging formulas, but it is important to be organized and systematic in your approach. Some tips to follow include:

  • Start by identifying the variable you are solving for and isolating it on one side of the equation.
  • Use algebraic principles, such as the distributive property, to manipulate the equation.
  • Be consistent with your steps and operations performed on both sides of the equation.
  • Double check your work by plugging the rearranged equation back into the original equation and simplifying.
Following these tips can help ensure that you rearrange the formula correctly.

Can I use a calculator to rearrange formulas?

While you can use a calculator to check your work, it is not recommended to use a calculator to rearrange formulas. This is because rearranging formulas involves understanding algebraic principles and operations, and using a calculator may not allow you to fully understand the process. It is best to practice rearranging formulas by hand to build your algebraic skills.

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