Question

9.9 cm 13 cm a. 16.3 b. 11.7 c. 9 d. 8.4 #1/9 next >

Explanation:

Step1: Assume it's a right - triangle problem

Use the Pythagorean theorem $a^{2}+b^{2}=c^{2}$, where $c$ is the hypotenuse and $a,b$ are the other two sides. If the hypotenuse $c = 13$ cm and one side $a=9.9$ cm, we want to find the other side $b$. Then $b=\sqrt{c^{2}-a^{2}}$.

Step2: Substitute the values

$b=\sqrt{13^{2}-9.9^{2}}=\sqrt{(13 + 9.9)(13 - 9.9)}=\sqrt{22.9\times3.1}=\sqrt{70.99}\approx 8.4$

Answer:

d. 8.4