Two different things u can do
Substitution:
X-9y=12
+9y +9y
X=9y+12
-3(9y+12)+9y=36
-27y-36+9y=36
+36 +36
-18y = 72
/-18 /-18
Y = -4
Or whatever this other I’ve is called
-3x-9y=36
-1(X-9y)=(12)-1
-3x-9y=36
-x+9y=-12
-4x=24
X= -6
The probability of the union of two events is the sum of their probability, minus the probability of their interserction:
If we plug the known values into this formula, we have
From which we can deduce
So, the probability of 
is a bit less than 
, we have to take away all events that belong to B as well:
The volume of a cylinder is pi r^ h
R (radius) is 5, h (height) is 2.
pi x 5^ x 2 = 157.080
Given:
Uniform distribution of length of classes between 45.0 to 55.0 minutes.
To determine the probability of selecting a class that runs between 51.5 to 51.75 minutes, find the median of the given upper and lower limit first:
45+55/2 = 50
So the highest number of instances is 50-minute class. If the probability of 50 is 0.5, then the probability of length of class between 51.5 to 51.75 minutes is near 0.5, approximately 0.45. <span />
