Answer:

Step-by-step explanation:
To find the cosine of <R, apply the following trigonometric ratio formula:

Adjacent = 3
Hypotenuse = √15
Plug in the values into the formula

Multiply the numerator and denominator by √15 to rationalize.




Answer:
10m+11
Step-by-step explanation:
Answer:
True
Step-by-step explanation:
There are an odd number of negative signs (3)
If there is an odd number it is negative, but if it is even then the result will be positive
Here's a deeper explanation
-1 times -1 is simply 1
Then 1 times -1 is -1
Our final answer is -1 so this is true.