Answer:
17
Step-by-step explanation:
since you are subtracting a negative number it reverses, so you actually ADD the two together
so, 12 1/2 + 4 1/2
add the whole numbers first;
12+4=16
then fractions:
1/2 + 1/2= 1
then all together;
16+1=17!
Answer:

Step-by-step explanation:
We can use either angle, but I'm going to use the one on the bottom. So, in order to find x, we need to use tangent. One side we know is the adjacent, and the side we don't know is the opposite, therefore we need tangent. Here's the equation:

Obviously, we can't have a root in our denominator, so we need to get rid of it somehow. Here's how:
We multiply the denominator of the fraction by
.
multiplied by itself is simply 2. Try it! We also want to multiply the numerator by
, but there isn't really a number we can use with that, so we'll just add it to the side. The equation you have now is:

Let's try to work this out now. Since the denominator is 2, we have to multiply both sides by it to find x.


We can plug 2 in for the x in the numerator now:

2 and 2 cancel out, so you get 1 in both the numerator and denominator. That's how we get our answer of 
Also, because this is a 45-45-90 triangle, you don't really have to do all that work. If it's a 45-45-90 triangle, both legs should be the same length. :)
Answer:
A) 24
Step-by-step explanation:
4!
4 x 3 x 2 x 1
24
So if they all add 4 hours to their time then they have:
Jeff 9
Mark 14
Karen 9
Costas 13
Brett 11
Nikki 9
Jack 11
so now to find the mean you add all the numbers together to get 76 and then you divide it by the number of people (7 people) so 76 divided by 7 equals 10.8571429 and that's the mean.
Now to find the median you put all the numbers in order from least to greatest: 9;9;9;11;11;13;14 and you take the number in the middle but since both 11 and 11 are in the middle you take the mean of them and the mean of them is 11 so the median of the numbers is 11
now to find the range you take the largest number (14) and you subtract the smallest number (9) so 14 - 9 is 5 so 5 is the range
and last the mode is the number that is repeated most out of all the numbers so the mode would be 9