Transcript Section 2.6 Alg.1 - Mukwonago Area School District

Section 2.7
Alg.1
How do you evaluate a
square root?
Review…
3(4x + 1) =
(5x – 3)4 =
x(4x + 7) =
Review…
5(x
7
+ 4) – 3x =
–(6x – 9) =
Review..
 Multiplicative
inverse is really just
multiplying by what…..
 What is the difference between additive
inverse and multiplicative inverse?
 What number are we trying to get when
we multiply a number and it’s
multiplicative inverse?
On a piece of paper….
(1)
(2)
(3)
(4)
(5)
-7(2x - 6) =
x(x – 8) =
9-(3x + 2) =
What is the multiplicative inverse of -6?
What is the multiplicative inverse of
−2
5
?
How do you read…
2
3
Squared Vs. Square Rootds
32 …. Is equal to 9…. but so is (−3)2
The square roots of 9 are 3 and (-3)
All positive real numbers have two square
roots:
a positive and a negative
How am I written?
A
square root is written with
a radical symbol….. √ .
The number under the
radical symbol is the
RADICAND.
What about zero?
The
square root
only has one
square root……..
ZERO
Evaluate the expressions…
±
√ 36 =
√
49 =
-
√ 36 =
√
- 36 =
Square root of a negative...
 What
two (same) numbers could you
multiply together to get a negative
number…..
 You can’t take the square root of a
negative number…. Because it
wouldn’t be a real number…
 In
further math classes…this is called an
imaginary number---it doesn’t exist!
Perfect Square…
 The
square of an
integer is called
the perfect
square.
 What
does it mean
to be an integer?
9
9
Approximating the square root
to the nearest integer….
±
√ 39
±
√15
±
√ 51
Word Problems…
 If
you want to buy a square wall poster of
the CHICAGO CUBS….That has an area of
225 square feet. Find the side length of
the wall poster!
?
?
Homework…
2.7
Worksheet!