Question

a rectangle has a width of 9 units and a length of 40 units. what is the length of a diagonal?
31 units
39 units
41 units
49 units

Explanation:

Step1: Apply Pythagorean theorem

In a rectangle, if the length is $l = 40$, the width is $w=9$, and the diagonal is $d$. According to the Pythagorean theorem $d^{2}=l^{2}+w^{2}$.

Step2: Substitute values

Substitute $l = 40$ and $w = 9$ into the formula: $d^{2}=40^{2}+9^{2}=1600 + 81=1681$.

Step3: Find the value of d

Take the square - root of 1681, $d=\sqrt{1681}=41$.

Answer:

C. 41 units