Once you have one angle, it’s a bit quicker to use the Law of Sines for the other angles. By the way, I recommend to high-school students to find the largest angle first, for then the ambiguity in using L of S for angles does not occur.
But $\angle OE'F=30°$, hence $E'F$ is the perpendicular bisector of $OC$. Finally, $BOC$ is an equilateral triangle (because $\angle OBC=\angle OCB=60°$), implying that line $E'F$ passes through $B$.
In the above diagram: Q is the center of the circle, PAT is a tangent to the circle, PR is parallel to AC, angle CAT = x. Prove that angle ABC = x. I started off by going 90 - x to find CAB. Then used co-interior angles to find AQR, and then found out BQR. I'm just curious, in this question, can I assume that QRB and ACB are right angled triangles?
When the triangle has a right angle, we can directly relate sides and angles using the right-triangle definitions of sine, cosine and tangent: $\sin \theta=\frac {\text {opposite}} {\text {hypotenuse}}$
How to find an angle of a non-right angle triangle when given two sides and an area? Ask Question Asked 10 years, 9 months ago Modified 10 years, 5 months ago
I'm trying to figure out the way to calculate the a angle value from given coordinates of three points as showed on the illustration below: I know how to calculate the a angle from the triangle's base length and its height, but in this case I'm stucked.
7 I bet this question has been asked a million times, but I can't find a straight answer. I need to find the length of the hypotenuse in a triangle where I have one side and all the angles. Example: Now in the above triangle I have the length of a = 20 and all the angles. How do I - from here - get the length of the hypotenuse (c)?
Think about similar triangles. Two similar triangles have exactly the same angles, but the sides are (generally) not the same length. That fact alone tells you that it is not possible to determine the lengths of the sides of a triangle if all you know is the angles -- you have to also know at least one side length in order to fix the scale.
The question says it all. Given a triangle, find its angles without a calculator. Is this even possible without tables or making tables? Summary: Is it possible to determine the inverse sin, cos...
