Question

A carpenter builds a rectangular bookcase that is 120 cm long and 62 cm tall. The carpenter uses two braces along the diagonals to support the bookcase.What is the length of the one of the braces, to the nearest tenth of a centimeter

Answer 1

Answer:

$135cm$

Step-by-step explanation:

We can use pythagoras' theorem to solve this.

$a^{2} +b^{2} =c^{2}$

let a be the long of the rectangle: a=120 cm

let b be the tall of the rectangle: b=62 cm

and c be the diagonal c=?

$a^{2} +b^{2} =c^{2}\\120^{2} +62^{2} =c^{2} \\c^{2} =14400+3844\\c^{2} =18244\\c=\sqrt{18244}\\c=135cm$

the length of the diagonal is  135cm