Question

10. If the length of a rectangular television screen is 20 inches and itsheight is 15 inches, what is the length of its diagonal, in inches? (2 points: 1point for correct answer, 1 point for showing your work)*Your answer

Answer 1

To find the length of a diagonal in a rectangle you use the Pythagoras theoren to find the length of the hypotenuse (x) in the right triangle formed by the diagonal length and height of the rectangle:

Pythagoras theorem:

`\begin{gathered} h^2=l^2+l^2 \\ h=\sqrt[]{l^2+l^2} \end{gathered}`

h is the hypotenuse

l are the legs of the right triangle

`\begin{gathered} x=\sqrt[]{(20in)^2+(15in)^2} \\ \\ x=\sqrt[]{400in^2+225in^2} \\ \\ x=\sqrt[]{625in^2} \\ \\ x=25in \end{gathered}`Then the length of the diagonal is 25 inches