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 jayinwww November 4th, 2016 04:12 PM

Having trouble with formulas (Equations & Transpositions)

Solve for A

b = 1/2h (A + C)

My first step is to minus C on both sides so I got

b - C = 1/2h A then i flip the 1/2 to 2/1 so it's b - C = 2h A

My second step is to divide both sides by 2h..

b-c/2h = A

But in my text book it says the answer is

A = 2b/h - C

I don't get it, where did i go wrong?

 skeeter November 4th, 2016 04:38 PM

Quote:
 Solve for A b = 1/2h (A + C)
your very first step is incorrect. you cannot subtract \$c\$ from inside the parentheses.

\$b = \dfrac{1}{2}h(a+c)\$

multiply both sides by 2 ...

\$2b = h(a+c)\$

divide both sides by \$h\$ ...

\$\dfrac{2b}{h}=a+c\$

subtract \$c\$ from both sides ...

\$\dfrac{2b}{h}-c=a\$

 deesuwalka November 8th, 2016 12:38 AM

\$b=\dfrac{1}{2}h(a+c)\$

Use inverse operations and leave \$a\$ at one side-

Here, \$2\$ is being divided, so multiply both sides by \$2\$

\$2b=h(a+c)\$

\$h\$ is being multiplied so divide both sides by \$h\$

\$\dfrac{2b}{h}=(a+c)\$

\$c\$ is being added so subtract \$c\$ from both sides

\$\dfrac{2b}{h}-c=a\$

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