Help with setting up word problem

[wato]

I'm having trouble setting this problem up as an equation, any help would be appreciated.

The Sum of a number and twice its square is 105. Find the number

 

[Daniel_Feldman]

Let the number be x. Then its square is x^2, and twice its square is 2x^2.

So x+2x^2=105.


From there, it's a basic quadratic equation.

 

[soroban]

Hello, wato!

Let x = the number . . . and I assume you know what "sum" means.

. . . The sum of a number and twice its square is 105.
. . . . . . . . . . . . . . . . . . .↓ . . . . . . . ↓ . . ↓ . . . . . .↓ . .↓
. . . . . . . . . . . . . . . . . . .x . . + . . .(2 )(x²) . . . . = .105

 

[stapel]

Note to soroban: How do you type those cute little "down arrow" characters?

Thanks!

Eliz.

 

[wato]

thank you very much!