Answer:
46
Explanation:
The geometry can be modeled by a right triangle. The diagonal measure is the hypotenuse, and the height is one leg. The width is the other leg, and can be found using the Pythagorean theorem.
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Pythagorean theorem
The relation between the leg lengths (a, b) and the hypotenuse (c) is ...
c² = a² +b²
Solving for b gives ...
b = √(c² -a²)
application
In this problem, we have c=55 and a=30. Then the width of the TV is ...
b = √(55² -30²) = √(3025 -900) = √2125
b ≈ 46.098
The width of the TV is about 46.