Question

ASAP Can someone help with this problems just I only need which formula do I used I just need for 4,5 and 6 just tell me the formulas for Law of Cosines

Answer 1

Explanation:

The formula for law of cosines is:

$a^{2} = b^{2} + c^{2} - 2bc(cosA)$

This is written at the top of your paper.

The angle is substituted where the capital A is. The side opposite to the angle is the angle name's lowercase. The two other sides are b and c.

Substitute all the information you know, then isolate the variable that you do not know.

When your formula is rearranged to look like this:

$\frac{a^{2} - b^{2} - c^{2}}{- 2bc} = (cosA)$

Solve the left side and punch into your calculator:

cos⁻¹(left side) to find the angle A.