Final answer:
Using the Pythagorean Theorem to calculate the diagonal of a screen with a width of 40 inches and a height of 32 inches, the screen size Emily needs to buy is approximately 51 inches diagonally, which rounds to 50 inches (Option C).
Step-by-step explanation:
To find the screen size that Emily needs to buy, we will calculate the diagonal measurement of the screen using the dimensions provided: 40 inches wide and 32 inches high. This can be done by applying the Pythagorean Theorem (a² + b² = c²), where 'a' and 'b' are the lengths of the screen's width and height while 'c' is the diagonal measurement.
Here is the calculation step-by-step:
- Substitute the given width (a=40 inches) and height (b=32 inches) into the Pythagorean Theorem equation: 40² + 32² = c².
- Calculate the squares: 1600 + 1024 = c².
- Add the results: 2624 = c².
- Take the square root of 2624 to find 'c': c ≈ 51.23 inches.
- Round to the nearest whole number: approximately 51 inches.
Therefore, Emily should look for a screen size that is close to 51 inches when measured diagonally, which rounds to the option C) 50 inches.