Standard form of a circle" (x-h)²+(y-k)²=r², (h,k) being the center, r being the radius.
in this case, h=-2, k=6, (x+2)²+(y-6)²=r²
use the point (-2,10) to find r: (-2+2)²+(10-6)²=r², r=4
so the equation of the circle is: (x+2)²+(y-6)²=4²
Answer:
x = 4 sqrt(5)
Step-by-step explanation:
Since this is a right triangle, we can use the Pythagorean theorem
a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
8^2 + x^2 = 12^2
64+ x^2 =144
Subtract 64 from each side
x^2 = 144-64
x^2 =80
Take the square root of each side
sqrt(x^2) = sqrt(80)
x = sqrt(16*5)
x = 4 sqrt(5)
If you divide 13.1 by 2.75 you'll get 4 plus a remainder so we know there are 4 stops at 2.75 intervals. 4*2.75=11. Subtract 11 from 13.1 and the last stretch would be 2.1 miles.
I hope this helped!
Answer:
Step-by-step explanation:
This is the sum of perfect cubes. There is a pattern that can be followed in order to get it factored properly. First let's figure out why this is in fact a sum of perfect cubes and how we can recognize it as such.
343 is a perfect cube. I can figure that out by going to my calculator and starting to raise each number, in order, to the third power. 1-cubed is 1, 2-cubed is 8, 3-cubed is 27, 4-cubed is 64, 5-cubed is 125, 6-cubed is 216, 7-cubed is 343. In doing that, not only did I determine that 343 is a perfect cube, but I also found that 216 is a perfect cube as well. Obviously, x-cubed and y-cubed are also both perfect cubes. The pattern is
(ax + by)(a^2x^2 - abxy + b^2y^2) where a is the cubed root of 343 and b is the cubed root of 216. a = 7, b = 6. Now we fill in the formula:
(7x + 6y)(7^2x^2 - (7)(6)xy +6^2y^2) which simplifies to
(7x + 6y)(49x^2 - 42xy + 36y^2)
Answer:
15 students are girls
Step-by-step explanation:
7+5=12
36÷12=3
3x5=15
