Question

Given: $sinA=\frac{3}{5}$

$cosA=\frac{m}{5}$ , m is ?

• A. $1$
• B. $2$
• C. $3$
• D. $4$

Answer 1

The correct option is D $4$

Given $\sin A=\frac{3}{5}$
$\sin A=\frac{P}{H}=\frac{3}{5}$
Thus, $P=3,H=5$
By Pythagoras Theorem,
$H^2=P^2+m^2$
$5^2=3^2+m^2$
$m=4$ cm
Now, $\cos A=\frac{m}{B}=\frac{4}{5}$