Right triangles appear naturally as halves of isosceles tria

Right triangles appear naturally as \"halves\" of isosceles triangles, so they can be used for solving such triangles. Exercises 6-8 illustrate this technique. Solve the triangle delta ABC, given a = b = 10 cm, and C^= 40 degree. Solve the triangle delta ABC, given a = b = 7 cm, and A^= 62 degree. Solve the triangle delta ABC, given a = b = 10 cm, and c = 8 cm.

Solution

6. a=b=10 cm

C=40

let A=B=x degree

Therefore 40+2x=180

x=70

Hence <A=<B=70 degree

In right triangle AMC, cos 70= x/10

x=10cos 70=3.42

Therefore c=2*3.42=6.48