# Thread: Help me with the angle

1. ## Help me with the angle

see the attactment

thank you

2. Hello helloying:

Draw a horizontal line through point E.

This forms some right triangles with leg measures of 10 and 17 because point E is vertically and horizontally centered inside the rectangle.

Therefore, the measure of half of angle BEC can be found using the inverse tangent function with the ratio 10/17.

Double the result.

Actually, you do not need the horizontal line because half of angle BEC is the same as the measure of angle BAE. And the ratio 20/34 simplifies to 10/17, which brings us back to the same input for the inverse tangent function.

Cheers,

~ Mark

3. Originally Posted by helloying
see the attactment

thank you
Is ABCD a rectangle? If so:

1. Split $\displaystyle \angle(BEC)$ into 2 equal parts: $\displaystyle \frac12 \angle(BEC)=\alpha$

2. $\displaystyle \tan(\alpha)=\dfrac{10}{17}~\implies~\alpha\approx 30.466^\circ$

3. Therefore: $\displaystyle \angle(BEC)\approx 60.9^\circ$