The unit rate you're trying to find is pages per day(or p/d), so the equation needs to have both a unit for pages and for days.
The equation we have is:

If they read 5,249 <em>pages</em>, then we can include the unit for pages in the equation.
Since we also know that <em>d</em> is the number of days it took, you can replace <em>d</em> with days.
The equation becomes:

Now that we have one variable, we can solve for <em>p/d</em>:

Thus it took them 181 days to read it all.
If Johnny read 5,249 pages over 181 days and the unit rate is pages per day(p/d), then the equation for finding <em>p/d</em> is:
Johnny read 29 pages per day.
<span>m∠CED = </span><span>1/2(m∠AOB + </span><span><span>m∠COD)</span> = 1/2(90° + 16°) = 1/2(106°) = 53°</span>
The problem says that <span>Brandon sights a helicopter above a building that is 200 feet away at an angle of elevation of 30 degrees. So, you can calculate the height asked, by following this procedure:
</span>
Tan(α)=Opposite leg/Adjacent leg
α=30°
Opposite leg=x
Adjacent leg=200 feet
When you substitute these values into the formula above (Tan(α)=Opposite leg/Adjacent leg), you have:
Tan(α)=Opposite leg/Adjacent leg
Tan(30°)=x/200
You must clear "x":
x=200xTan(30°)
Therefore, the value of "x" is:
x=115 feet
<span>
How high above the ground the is the helicopter?
The answer is: 115 feet</span>