Question

label the sides and angle and calculate the missing values in the triangle:

Explanation:

Step1: Find the hypotenuse (H)

Use the Pythagorean theorem $H=\sqrt{A^{2}+O^{2}}$, where $A = 1.98$ and $O=1.61$.
$H=\sqrt{(1.98)^{2}+(1.61)^{2}}=\sqrt{3.9204 + 2.5921}=\sqrt{6.5125}\approx 2.55$

Step2: Find the angle $\theta$

Use the tangent - function $\tan\theta=\frac{O}{A}$.
$\tan\theta=\frac{1.61}{1.98}\approx0.8131$. Then $\theta=\arctan(0.8131)\approx39.1^{\circ}$

Answer:

$H\approx2.55$, $\theta\approx39.1^{\circ}$