Answer:
Step-by-step explanation:
Join A and C and B and D. And add numbers to the angles formed on one of the diagonal
In triangles ABC and ADC,
Angle 1 = Angle 4
Angle 3 = Angle 2
AC = AC
Therefore, triangle ABC=ADC
Since, ABC=ADC
Similarly, triangle ABD= triangle CDB
Therefore, AB=CD and BC=DA
Assuming the man works 8 hours straight without breaks:
25% is the same as 1/4 of something.
So, we just have to figure out what 1/4 (one quarter) of 8 equals.
You can think of it as a pizza cut into 8 slices. One slice is equivalent to one hour for the patrolman.
If we take away 1/2 (half) of the pizza, we have 4 slices, right? Since we start with 8 slices, half of that equals 4 slices. In other words, 50% (half) of the pizza = 4 slices.
Now, 25% (one quarter) of the pizza will equal half of what is left:
If we know that 50%=4 slices (or 4 hours), then 25% must be 2 slices (or 2 hours).
That's it! 25% of 8 hours = 2 hours.
***So, the patrolman spends 2 hours each day completing paperwork.***
Lets check our work:
We know 8 hours (or 8 slices)= 100%
(We know this because
8 slices = 1 whole pizza, or 100% of a pizza. Similarly,
8 hours = 1 whole shift or 100% of the man's shift ).
So
25% + 25% + 25% + 25% = 100%
If 100% of the mans shift = 8 hours:
2+2+2+2 = 8
It checks out!
Hope this helps!
Use the following identity:
cos(2x)=1-2sin^2(x)
Password to what exactly?