Triangle side/length

Question

Side a=5,angle a is 45

angle c = 90 degrees

whats angle b? What's length of angle b and c?

 

side c=7, angle c=120, angle b=40 degrees

whats angle a? What's length of a and b?

Answer 1

(a)

Step 1:

measures angles are and and side .

Sine rule is .

Substitute , and in the sine rule.

.

Find the length of angle .

angle is  .

Substitute and in above formula.

Length of angle is .

Step 2:

Find length of .

Consider .

Side length of is .

Find length of .

Substitute in the sine rule.

Consider .

Side length of is .

Solution :

Length of angle is

Sides is lengths are and .

Answer 2

(b)

Step 1:

measures angles are and and side .

Sine rule is .

Substitute and in the sine rule.

Find the length of angle .

Substitute in .

Length of angle is .

Find length of .

Find length of .

Substitute in the sine rule.

Solution:

Length of angle is .

Sides is lengths are