Solve for the angles in a triangle

In summary, to find the missing angle in a triangle, you can use the sum of all angles being 180 degrees. The Pythagorean theorem cannot be used to solve for angles, but other methods like the law of cosines or law of sines can. Acute triangles have all angles less than 90 degrees, while obtuse triangles have one angle greater than 90 degrees. Trigonometric ratios can also be used to solve for angles, but you need to know one side length and one angle measure. There are two special cases: the right triangle and the equilateral triangle, with the right triangle having one angle of 90 degrees and the equilateral triangle having all angles measuring 60 degrees.
  • #1
gazparkin
17
0
Hi,

Could someone check that I'm right with this one, or put me right! I've worked the value out as

x=30 and y (2x) = 60. I've come to this as I think it's an isosceles triangle so the base angles would be equal. Am I right?

Thank you!

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  • #2
60 + x + y = 180

if y = 2x ...

60 + x + 2x = 180

try again ...
 
  • #3
Is it x = 40 and y =80??
 
  • #4
gazparkin said:
Is it x = 40 and y =80??

Yes, that's correct.
 
  • #5
catmitt98 said:
Yes, that's correct.

Thank you for your help.
 

1. What is the sum of the angles in a triangle?

The sum of the angles in a triangle is always 180 degrees. This is known as the triangle angle sum theorem.

2. How do you find the missing angle in a triangle?

To find the missing angle in a triangle, you can use the triangle angle sum theorem. Subtract the known angles from 180 degrees to find the missing angle.

3. Can you solve for the angles in a triangle if you only know the lengths of the sides?

Yes, you can use the Law of Cosines or the Law of Sines to solve for the angles in a triangle if you know the lengths of the sides.

4. What is the difference between an acute, obtuse, and right triangle?

An acute triangle has all angles less than 90 degrees, an obtuse triangle has one angle greater than 90 degrees, and a right triangle has one angle that is exactly 90 degrees.

5. Is it possible for a triangle to have more than one obtuse angle?

No, a triangle can only have one obtuse angle. This is because the sum of the angles in a triangle is always 180 degrees, and if there were two obtuse angles, the sum would be greater than 180 degrees.

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