Question

CAN SOMEONE HELP PLEASE m4A=42°, b=10, c= 12. What is the length of a to the nearest tenth?

Answer 1

Answer:

a = 8.1

Step-by-step explanation:

Use the cosine rule:

$a = \sqrt{b^2 + c^2 -2 bc \space\ cosA }$

Substituting the values:

$a = \sqrt{10^2 + 12^2 -2(10)(12) \space\ cos 42 \textdegree\ }$

⇒ $a = \sqrt{4 \space\ cos 42\textdegree\ }$

⇒ $a = 8.1$