Answer:
Step-by-step explanation:
(x²-6x)+(y²+8y)=-21
(x²-6x+9)+(y²+8y+16)=-21+9+16
(x-3)²+(y+4)²=4
center=(3,-4),radius=√4=2
Answer:
1. <u>+12x</u> and <u>15</u>
2. <u>14x</u>
3. <u>2</u>
Step-by-step explanation:
Step 1: Distribute -3
To distribute -3, you would multiply both -4x and -5 by -3, changing them to 12x and 15
Step 2: Combine 12x and 2x
Then you would combine like terms, meaning that you would add 12x and 2x, creating 14x.
Step 3: Combine 15 and -13
You would finish combining like terms by adding 15 to -13, creating 2
Answer:
Step-by-step explanation:
First we need to set this ratio up in the coordinate plane. Because this is tangent, the 3 goes opposite the reference angle and the 4 goes along the x-axis, adjacent to the reference angle. We see that we are missing the third side of the triangle when we do this, namely the hypotenuse. We use Pythagorean's Theorem to find that this side is 5. Now we have to deal with the identities for each sin(2A) and cos(2A).
sin(2A) = 2sin(A)cos(A)
We know from the triangle we drew in the coordinate plane that
and
so we fill in the formula accordingly and then simplify:

cos(2A) has 3 identities; I just picked the one I thought would be easiest to use and went with that one. Regardless of which one you pick you will get the same answer as long as you do the math correctly.
and filling in the formula:

I'm not sure why you have 7/2 there...
Answer:

Step-by-step explanation:
To find the LCM of 1,2,12,30,84,165 you must first find the prime factors of 12,30,84 and 165
12| 2 30| 2 84| 2 165| 3
6 | 2 15 | 3 42| 2 55 | 5
3 | 3 5 | 5 21 | 3 11 | 11
1 1 7 | 7 1
1

Now we look for common and uncommon factors with their greatest exponent
LCM(1,2,12,30,84,165)
Common factors with their greatest exponent: 
Uncommon factors with their greatest exponent: 

9514 1404 393
Answer:
angle zoy is 70°, an acute angle
Step-by-step explanation:
Each of the 18 spaces around the 180° semicircle identifies 10° of arc. There are 7 spaces between rays z and y, so the angle zoy is 70°. It is less than 90°, so it is an <em>acute angle</em>.