When a triangle is a 45-45-90 triangle, the following rules apply:
-the 2 legs are equal lengths
- the length of the hypotenuse is: the square root of 2 x the length of a leg.
- the length of the leg is: hypotenuse divided by the square root of 2.
if the hypotenuse is 10, then 10 divided by the square root of 2 is how you find the leg.
the square root of 2 is <span>1.41421356237.
10 divided by </span>1.41421356237 is <span>7.07106781188, which can be rounded to about 7.1. The length of one leg is about 7.1 units!</span>
In a ratio of 7:3, for every 7 adults you have 3 children. So 30% of the total are children. I.e. if you have 10 people .7 times (10) are adults or 7 and .3 times (10) are children or 3. So for 370 people, .3 times 370 are children, or 111.
Answer:
The area is 
Step-by-step explanation:
rectangle in the middle; 24
both triangles on the side; 56
In total; 80
Answer:
unreadable score = 35
Step-by-step explanation:
We are trying to find the score of one exam that is no longer readable, let's give that score the name "x". we can also give the addition of the rest of 9 readable s scores the letter "R".
There are two things we know, and for which we are going to create equations containing the unknowns "x", and "R":
1) The mean score of ALL exams (including the unreadable one) is 80
so the equation to represent this statement is:
mean of ALL exams = 80
By writing the mean of ALL scores (as the total of all scores added including "x") we can re-write the equation as:

since the mean is the addition of all values divided the total number of exams.
in a similar way we can write what the mean of just the readable exams is:
(notice that this time we don't include the grade x in the addition, and we divide by 9 instead of 10 because only 9 exams are being considered for this mean.
Based on the equation above, we can find what "R" is by multiplying both sides by 9:

Therefore we can now use this value of R in the very first equation we created, and solve for "x":
