Post on 07-Feb-2021
transcript
Square Roots of Non-Perfect Squares
Ms. Pempengco
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A non-perfect square is a number that cannot be written as a product of two equal numbers.
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2 3?2.5
To estimate non-perfect squares, we visualize a number line and the closest perfect square on each side of the number we’re looking for.
Ex 1: To find 7.5
From the diagram, an approximate value is 7.5 ≈ 2.7
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Method 1: Approximate the fraction using benchmarks
Method 2: Change to a decimal and approximate the decimal using benchmarks
Which is more accurate? Which should we use?
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Method 1: Approximate the fraction using benchmarks
Method 2: Change to a decimal and approximate the decimal using benchmarks
Which is more accurate? Which should we use?5
Now check our answer with a calculator
► It’s more precise to
change the fraction to a decimal
estimate the square root of the decimal number
Ex 3: What is 55
10?
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10 and 111
4and
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2
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Determine a decimal or a fraction whose a square root is between:
The variables may differ:
𝑎2+ 𝑏2= 𝑐2
𝑎2+ 𝑏2= 𝑟2
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Ex 1: A ladder is 6.1 m long. The distance from the base of the ladder to the wall is 1.5 m. How far up the wall will the ladder reach? Hint: sketch a diagram.
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Ex 2: The slope face of this ramp is to be covered in carpet.
a) Estimate the length of the ramp to the nearest tenth of a meter
b) Use a calculator to check the answer
c) Calculate the area of carpet needed
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