SOLUTION: Twice the square of a certain postive number is 144 more than twice the number. What is the number? Really looking for help on how to set up.... can solve but can't seem to fig

Question 195933: Twice the square of a certain postive number is 144 more than twice the number. What is the number?
Really looking for help on how to set up.... can solve but can't seem to figure out how to set the thing up. Thanks.
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
You're probably hung up on the translation:

"Twice the square of a certain postive number" ---->
"is" ---> =
"144 more than twice the number" ---->

So the full translation is

Start with the given equation.

Get all terms to the left side.

Notice we have a quadratic equation in the form of where , , and

Let's use the quadratic formula to solve for x

Start with the quadratic formula

Plug in , , and

Negate to get .

Square to get .

Multiply to get

Rewrite as

Add to to get

Multiply and to get .

Take the square root of to get .

or Break up the expression.

or Combine like terms.

or Simplify.

Remember, the problem stated that the number is positive. So the only answer is
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