Question

what is the perimeter? if necessary, round to the nearest tenth.
□ centimeters
10 cm
5.6 cm
a

Explanation:

Step1: Find side length $a$ via Pythagoras

$$a = \sqrt{10^2 - 5.6^2} = \sqrt{100 - 31.36} = \sqrt{68.64} \approx 8.285$$

Step2: Sum all sides for perimeter

$$\text{Perimeter} = 5.6 + 10 + 8.285 \approx 23.885$$

Step3: Round to nearest tenth

$$23.885 \approx 23.9$$

Answer:

23.9 centimeters