Question

a certain television is advertised as a 38-inch tv (the diagonal length). if the height of the tv is 25 inches, how wide is the tv? round to the nearest tenth of an inch.

Explanation:

Step1: Apply Pythagorean theorem

Let $w$ = width, $h=25$, $d=38$.
$$w^2 + h^2 = d^2$$

Step2: Isolate width term

$$w^2 = d^2 - h^2$$

Step3: Substitute values

$$w^2 = 38^2 - 25^2 = 1444 - 625 = 819$$

Step4: Solve for width

$$w = \sqrt{819} \approx 28.62$$

Step5: Round to nearest tenth

Round $28.62$ to one decimal place.

Answer:

28.6 inches