Q.In a right angled triangle, the acute angles are in the ratio 4:5. Find the angles of the triangle in degree and radian.

Step 1: In a right triangle the two acute angles sum to $90°$ (since one angle is already $90°$ and the total is $180°$).

Step 2: Split $90°$ in ratio $4:5$: let the angles be $4k$ and $5k$. Then $4k+5k=90° \Rightarrow 9k=90° \Rightarrow k=10°$. Angles: $4k=40°$, $5k=50°$. …

Use the fact that the acute angles of a right triangle sum to 90°, split that sum in th …

• Splitting 180° instead of 90° in the given ratio, forgetting one angle is already fixed at 90°. …