Question

A certain television is advertised as a 5-inch TV (the diagonal length). If the width of

the TV is 4 inches, how many inches tall is the TV?

Answer 1

TV is 3 inches tall.

Explanation:

Given: Diagonal length of TV is 5 inch

Width of TV is 4 inches.

Considering TV to be in rectangle shape.

Lets assume the TV height to be "x"

Diagonal form a right angle triangle as shown on picture attached.

∴ using pathagorean theoram to find the height of TV.

`h^(2) = a^(2) + b^(2)`, where h is hypotenous, a is width or adjacent and b is height or opposite side.

∴
`5^(2) = 4^(2) + x^(2)`

⇒
`25= 16+x^(2)`

subtracting both side by 16

⇒
`25-16= x^(2)`

⇒
`x^(2) = 9`

Taking sqaure root on both side.

Remember, √a²= a

⇒
`x= √(9)`

∴
`x= 3`

Hence, the height of TV is 3 inches.