How to find the angles of a triangle?

Probably everyone knows such a simple figure,consisting of three interconnected lines, like a triangle. From the school program is still known to everyone how to find the sides of the triangle, but for today few people remember those true rules and formulas. And refresh it in memory, it would not hurt at all, because sometimes it is just necessary to know the rules how to find angles in a triangle in order to determine a certain distance in everyday life.

Let's try to remember the Pythagorean Theorem,which indicates that the square of the hypotenuse is equal to the sum of the squares of the two legs. We refer to the sides of a triangle as crosspieces that intersect at an angle of 90 degrees. Hypotenuse is the side between them. Knowing the length of the two sides, you can calculate the third of the formula.

There are several more rules, how to find the thirdangle of a triangle, but these theorems are slightly more complicated. Proceeding from the sine theorem, the sides of the triangle are proportional to the sines of the opposing angles. That is, there is a formula according to which the radius of a circle circumscribed about a triangle, multiplied by two, is equal to the ratio of each side of the triangle to the sine of the opposite angle. Knowing the data, you can calculate the missing sides. One can also turn to the cosine theorem, which generalizes the very theorem of Pythagoras. The square of one side is equal to the sum of the squares of the other two minus the doubled product of these sides by the cosine of the angle between them.

The most important of all these formulas is to be able to correctly substitute the data and find the unknown, since the incorrect derivation of the unknown will not give the correct result.