<span>the probability of an event and the probability of its complement add up to 1
because the total events are the even it self and its compliment, so its probability equal to 1 because these are all the possible events that will occur. for example a coin toss, an event head will happen 0.5, and its complement is tails which will also happens 0.5</span>
Roxanna earns $18 per hour.
If Roxanna earns $72 in 4 hours, then the equation to find how much she earns per hour is:
72/4 = x
x = 18
Hope this helps! Feel free to ask questions.
<span> b
(2a + (2 • —)) - 5c = 0
</span>
Answer: 
Step-by-step explanation:
Because an angle inscribed in a semicircle is a right angle, 
So, as angles in a triangle add to 180 degrees, 
The length (L) of the rectangle can be written as a function of the width (W)

:
Now since we know Area = Width*Length, we can write the area as a function of the width:

Distributing the W inside the parentheses we have:

We know the area is 54 ft^2, so we can rewrite it as:

Now solve for W by factoring (or by applying the quadratic formula):

Factor out a common 2W from the first two terms and a 9 from the last two terms:

Regroup the terms to get our fully factored equation:

This gives us the roots W = 6 and W = -9/2, but width can't be negative so we have width = 6 ft. Then remember that the length L = 2W - 3, so our length is:

So now we know that our rectangle is 9 feet long and 6 feet wide.