Question

The size of a tv is identified by the length of its diagonal. a new tv is being advertised as a 70 in. tv. the tv screen is in the shape of a rectangle with a 59.5 in. width.
what is the height of the tv screen, rounded to the nearest tenth of an inch?

Answer 1

Using the Pythagorean theorem:

a^2 + b^2 = c^2  ( a and b are the sides and c is the diagonal)

59.5^2 + b^2 = 70^2

Simplify:

3540.25 + b^2 = 4900

Subtract 3540.25 from both sides:

b^2 = 1359.75

Take the square root of both sides:

b = 36.874

Rounded to the nearest tenth = 36.9 inches.