Answer:
D
Step-by-step explanation:
Using cosine formula, we have
Answer:
15
Step-by-step explanation:
Let us first write an equation where the unknown number is represented with variable x. <em>The sum of a fifth of x and two is five:</em>

Great! Let's solve for x by isolating the variable.

<u>Therefore, the unknown number is 15.</u>
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<em>I hope this helps! Let me know if you have any questions :)</em>
If you solve for x the answer is x<-8
Step-by-step explanation:
angle 2 = 180-39= 141°
angle 2 = 141°