# Thread: The Area of a Triangle

1. ## The Area of a Triangle

Hi my first post on this forum, I am having trouble wiht work out the area of a triangle, not you standard formula 'half base times height though'

The formula for this is Area = 1/2ab sin C two sides and included angle

does anyone know how to solve these problems if so post here thankyou

2. Originally Posted by Needhelpatmaths
Hi my first post on this forum, I am having trouble wiht work out the area of a triangle, not you standard formula 'half base times height though'

The formula for this is Area = 1/2ab sin C two sides and included angle

does anyone know how to solve these problems if so post here thankyou
Yes, the another formula for area of a triangle is $= \frac{1}{2} ab \sin C$.

where a and b are two sides and C is included angle. Please mention the exact problem. Do you need to prove this formula or what???

3. ## No

No I just have to answer some problems but I am not sure on how to do it, I have looked at the example over and over again but it is not sinking in.

Would you like an example of the question?

4. Originally Posted by Needhelpatmaths
No I just have to answer some problems but I am not sure on how to do it, I have looked at the example over and over again but it is not sinking in.

Would you like an example of the question?
Yes please provide an exact question, so that it can be answered.

5. ## ok

Example

Find the area of the triangle ABC where a = 14 cm, c = 15 cm and angle B = 48 degrees

6. Find the area of the triangle ABC where a = 14 cm, c = 15 cm and angle B = 48 degrees

A = (0.5) * (14) * (15) * sin(48)

Just have to multiply those 4 factors together, the product will be your area in square centimeters.

7. The formula for arrea of a triangle is

Area of triangle ABC $= \frac{1}{2}ab \;\sin C$

Area of triangle ABC $= \frac{1}{2}bc \;\sin A$

Area of triangle ABC $= \frac{1}{2}ca \;\sin B$

8. ## Thankyou

thankyou both for helping me I can now get this work done

9. A good exercises will be to demostrate this formula, then you will know when used it

10. This formula applies basically to non right angle triangles.