Am I missing something in the formula?

Question

I have started wirking with triangles, & I'm trying to remember:

Sine = Opposite / Hypotenuse

Cosine = Adjacent / Hypotenuse

Tangent = Opposite / Adjacent

Perimeter = Sum of it's sides

Area = Base times Height

 

Do I have all of these correct?

Answer 1

For triangles, the area =basexheight / 2

Pythagorean theorem is also important:

c^2=a^2 +b^2

In a right triangle the square of the hypotenuse is the sum of the squares of the other two sides.

Answer 2

idk sorry