Exploring Square Roots and Irrational Numbers

1
Exploring Square Roots and Irrational Numbers
COURSE 3 LESSON 4-8
Find the two square roots of each number.
a. 81
9 9 81
9 (9) 81
The two square roots of 81 are 9 and 9.
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2
Exploring Square Roots and Irrational Numbers
COURSE 3 LESSON 4-8
Estimate the value of 70 to the nearest
integer.
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3
Exploring Square Roots and Irrational Numbers
COURSE 3 LESSON 4-8
The math class drops a small ball from the top
of a stairwell. They measure the distance to the
basement as 48 feet. Use the formula d 16t2 to
find how long it takes the ball to fall.
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4
Exploring Square Roots and Irrational Numbers
COURSE 3 LESSON 4-8
(continued)
It takes about 1.7 seconds for the ball to fall
48 ft.
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5
Exploring Square Roots and Irrational Numbers
COURSE 3 LESSON 4-8
Identify each number as rational or irrational.
Explain.
Rational the decimal repeats.
Irrational 90 is not a perfect square.
Irrational the decimal does not terminate or
repeat.
d. 6.36366366636666. . .
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Exploring Square Roots and Irrational Numbers
COURSE 3 LESSON 4-8
1. Find the two square roots of 400. 2. Estimate
34 to the nearest integer. 3. Using d 16t
2, find how long it takes a skydiver to fall 676
ft from an airplane. 4. Is rational or
irrational? Explain.
20 and 20
6
6.5 s
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