Answer:
10
β
Step-by-step explanation:
We can find this two ways, first by seeing in the step after it, cosines are canceled out. Since you already have 10β on the next step, you can assume that (since only the cosines changed and the cosine next ot the blank was removed), the value is 10β.
You can also use double angle formulas from the previous step:
(sin(2β) = 2 sin(β) cos(β))and find that:
5 sin (2β) sin(β) = 5 * (2 sin(β) cos(β)) sin(β)) = (10 sin(β) sin(β)) cos(β) =
10β cos(β)
But since cos(β) is already present, we can see that the answer is 10β
Answer:
225
Step-by-step explanation:
3 out of 5 is .6 is u multiply .6 by 375 you get 225
x = liters of 20% solution
Mixing the 20% solution with the 60 L of 90% solution gives a new mixture with volume (x + 60) L. Each L of the 20% solution contributes 0.2 L of alcohol and thus a total of 0.2x L of alcohol, while the 60 L of 90% solution contributes 54 L of alcohol.
We want the concentration of the new mixture to be 80%, so we require
Solve for x:
So you will need 30 L of the 20% solution.
Answer:
Step-by-step explanation:
e = earrings and b = bracelets
so each earring cost 5 bucks.....5e
and each bracelet cost 7 bucks.....7b
and she hopes to make $ 300...
so ur equation is : 5e + 7b = 300 <===
Answer: 17
Step-by-step explanation: ok so first to find the mean you add all the numbers then divide by how many numbers there is so basically 18 plus 15 plus 20 plus 15 then divide by 4 because there is 4 numbers and once you do that it is 17
