Use the change-of-basis identity,

to write

Use the product-to-sum identity,

to write

Redistribute the factors on the left side as

and simplify to

Now expand the right side:

Simplify and rewrite using the logarithm properties mentioned earlier.





(C)
Most graphing calculators will do weighted averages pretty easily. It is mostly a matter of data entry.
mx = -2
my = 10
(x, y) = (mx, my)/10 = (-0.2, 1)
Answer:
3/2y -5
Step-by-step explanation:
-1/2 (-3y+10)
Distribute
-1/2* -3y + -1/2*10
3/2y -5
So we know there are 5 red and 12 silver marbles, together making 16 marbles.
This would mean that there is a 5/17 chance of choosing a red marble.
When you do the math to convert 5/17 into a decimal, it turns into being a .29 chance.
Convert .29 into a decimal, and you know that you have a 29% chance of grabbing a red marble.
Hope this helped!
- Kathryn Irene