Question

Use the law of cosines round to the nearest tenths

Answer 1

Answer:

x = 11.5

Step-by-step explanation:

Formula

a^2 = b^2 + c^2 - 2*b*c * cos(A)                     Substitute givens in formula

Givens

• b = 31
• c = 26
• A = 21o
• a = x                                                      Let a = x to present the formula in it's most normal way

Solution

a^2 = 31^2 + 26^2 - 2 * 31 * 26 * cos(21)       Find -2*31*26*cos(21)

a^2 = 961 + 676  -1504.93                             Combine

a^2 = 1637 -1504.93                                      Combine again

a^2 = 132.07                                                   Take the √ on both sides

√a^2 = √132.07

a = 11.5 Rounded.

Answer

x = 11.5