Question

Consider right triangle ABC, with C = 90 degrees. If a= 21 and c=29, find a.?

Answer 1

Step 1:

In right angle triangle , angle and length of the sides are .

In right angle triangle, opposite side to the right angle is hypotenuse.

Opposite side to the angle is .

From the Pythagorean theorem,

Substitute in above expression.

Side .

Step 2:

From the cosine rule, .

Substitute in above formula.

Step 3:

In a triangle , sum of the three angles is .

Substitute in above formula.

Soluiton:

, .