Two negatives make a positive so, -13 - (-49) equals -13 + 49, or 49-13, they are all the same thing, all equal to 36.
Answer: 8 pi
Step-by-step explanation: So we know that area of a circle is pi times r^2 so if we reverse that formula it would be square root of 16 pi which would be 4 pi and divide by pi so the radius is 4. And we know that the formula for circumference is 2 times pi times r, so 2 times 4 times pi is 8 pi. 8 pi is the cIrcumference! :)
Answer:
9 x (x +5) = 185
Step-by-step explanation:
I'm pretty sure this is how you write it
There are 6! = 720 ways of arranging the lamps.
If the leftmost lamp is red, there are 3 choices of lamp in the leftmost position, and the remaining 5 can be placed in any order, so there are 3×5! = 360 ways of arranging the lamps and the leftmost is red.
Hence there is a 360/720 = 1/2 probability that the leftmost lamp is red.
Ignoring lamp color for the moment, the probability of arranging 3 lit lamps and 3 unlit lamps is the same, 1/2.
Since Ryan arranges the lamps randomly by color, then turns 3 of them on randomly, the two events are independent. So
P(leftmost red AND leftmost lit) = P(red) × P(lit) = 1/2² = 1/4
