Answer:
113.04 cm.
Step-by-step explanation:
Step 1: <u>Formula/explain</u>
To find the area of a circle, multiply the radius by itself twice, then multiply the product pi.

Step 2: <u>Solve</u>
According to the word problem, the circle has a diameter of 12. This means it has a radius of 6.
Now, we plug the numbers into formula.

Step 3: <u>Conclude</u>
Therefore, the area of this circle is 113.04 cm.
Sin⁻¹ √2 = 1/√2 = 1(√2) / (√2)(√2) = √2/2
Aye man , who wants to give me points
I am going to explain this using the substitution method, considering it appears to be the best in this situation.
We know (from the bottom equation) that y can equal 3x+20. Using this knowledge, we substitute the y in the top equation for 3x+20. Now, we have an equation that looks like this:
3x+20=x^2+2x
Now we need to move x to one side and then do some radicals (square roots).
Subtract the 2x on the right (since it is smaller, negatives = NONONO), which will give you
x+20=x^2
Now, we take the square root of both sides to get
rad(x+20)=x
Now we have to simplify. 20 doesn't have a square root, but 4 goes into 20, and 4 has a square root of 2. This now becomes
2rad(x+5)
This doesn't simplify any further... we have a problem... no way to isolate x as far as my knowledge goes... Sorry, can't help you any further than that, but another person or your teacher might be able to. R.I.P...
If you have a calculator, you can use the inverse cos " cos⁻¹ " key. Many upper level books write that as Arccos so as not to confuse you with a negative exponent. We do that because if you take the cosine of any angle, and then the inverse cosine of any angle, it leads you back to the original angle. Think of it as a big "UNDO" button.
To one decimal place, that result is 61.6 degrees.