Answer:
50 inches
Explanation:
Using the Pythagorean theorem, we can find the length of the diagonal of the TV:
diagonal^2 = height^2 + width^2
diagonal^2 = 30^2 + 40^2
diagonal^2 = 900 + 1600
diagonal^2 = 2500
Taking the square root of both sides, we get:
diagonal = sqrt(2500)
diagonal = 50
Therefore, the length of the diagonal of the TV is 50 inches.