One polynomial identity that crops up often in various areas is the difference of squares identity:
A2-b2=(a-b) (a+b)
We meet this in the context of rationalising denominators.
Before you begin this lesson, please print the accompanying document, Unit Rates in Everyday Life].
Have you ever been at the grocery store and stood, staring, at two different sizes of the same item wondering which one is the better deal? If so, you are not alone. A UNIT RATE could help you out when this happens and make your purchasing decision an easy one.
In this lesson, you will learn what UNIT RATES are and how to apply them in everyday comparison situations. Click the links below and complete the appropriate sections of the Unit Rates handout.
[Note: The links below were created using the Livescribe Pulse Smartpen. If you have never watched Livescribe media before, take a few minutes to watch this very brief Livescribe orientation]
<span>What is a UNIT RATE – definitionView some examples of Unit RatesSee a process to compute Unit Rates</span>
<span>Answer: -4.88691778Solution:1.Write down the number of degrees you want to convert to radians Given Degree = -280° The formula to convert degrees to radian measure is:Radian = degree x π/180 2. Multiply the number of degrees by π/180. Think of it like multiplying two fractions: the first fraction has the number of degrees in the numerator and "1" in the denominator, and the second fraction has π in the numerator and 180 in the denominator. -280 x π/180 = -280π/1803. Find the largest number that can evenly divide into the numerator and denominator of each fraction and use it to simplify each fraction. The largest number for 280 is 20.-280 x π/180 = -280π/180 ÷ 20/20 = -14π /9 4. Then multiply the numerator by 3.14159 because pi or π is equivalent to 3.14159, -14x 3.14159= -43.982265. To get the radian measure, we will divide -43.98226 by 9. -43.98226/9= -4.88691778
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Using 3.14 for PI.
The radius of a ball and the can is half the diameter = 1.25
The height of the can is the height of 3 diameters = 7.5
Volume of one tennis ball:
4/3 x PI x 1.25^3 = 8.18 cubic inches.
Volume of 3 tennis balls: 3 x 8.18 = 24.54 cubic inches.
Volume of can:
PI x 1.25^2 x 7.5 = 36.80 cubic inches.
Space = 36.80 - 24.54 = 12.26 cubic inches.
