Question

The equation sin(40)=b\20 can be used to determine the length of the line segment ac. What is the length of ac? Round to the nearest tenth. 11.8cm 12.9cm 14.9cm 15.3cm

Answer 1

Answer: (b)

Explanation:

Given

The given equation can be used to determine the length of the line segment AC i.e.

$\Rightarrow \sin (40^{\circ})=\dfrac{b}{20}\\\\\Rightarrow b=20\sin (40^{\circ})$

Where, $b=\text{length of ac}$

$\therefore b=20\times 0.642\\\Rightarrow b=12.85\approx 12.9\ cm$

Hence, option (b) is correct.