
Home > A2C > Chapter 8 > Lesson 8.2.2 > Problem 8-136
8-136.
Use the Law of Cosines.
C2 = A2 + B2 − 2ABcos(c)
(x)2 = (15)2 + (21)2 − 2(15)(21)cos(40°)
x ≈ 13.542
Find the last angle, then use the Law of Sines.
x ≈ 68.770
Use the Law of Cosines.
C2 = A2 + B2 − 2ABcos(c)
(x)2 = (15)2 + (21)2 − 2(15)(21)cos(40°)
x ≈ 13.542
Find the last angle, then use the Law of Sines.
x ≈ 68.770