Final answer:
To find the unknown number, set up the equation √(2x + 1) = 5, square both sides to get 2x + 1 = 25, and solve for x, which gives us x = 12.
Step-by-step explanation:
The student is asking for help to find a number where if you take twice the number, add one, and then take the square root, the result will be 5. To solve this, we translate the word problem into a mathematical equation and then solve for the unknown number.
Step-by-Step Solution:
- Let the unknown number be x.
- Write down the equation based on the problem: √(2x + 1) = 5.
- Square both sides to remove the square root: (2x + 1) = 5².
- Calculate the square of 5: 5² = 25.
- Replace 5² with 25 in the equation: (2x + 1) = 25.
- Subtract 1 from both sides: 2x = 24.
- Divide both sides by 2 to solve for x: x = 24 / 2.
- The solution is x = 12, which is the number the student is looking for.
This process uses algebraic methods and knowledge of exponents, particularly the concept that squaring a number is the same as raising it to the power of 2, to find the answer.