Transcript 10x 2 -18x - TeacherWeb

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• Parabola. This is what anything with an
x2 in it looks like graphed.
• The bottom (or top) is the vertex. (Also
called the minimum or maximum
point).
Scientific Notation on TAKS
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If Jupiter is GREATER than the earth, are you going to
multiply or divide by 11.2 to find earth?_____
So _______ 8.9 by 11.2 and you get ____ x 104
And now change that to scientific notation.
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Combined? Do you
add, subtract,
multiply or divide?
_____ Show work:
Which don’t open up?
_____ and ____
Graph the other
two…which is widest:
_____________
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Looks can be deceiving.
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Reading a Quadratic Graph
This was on the benchmark
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What is the “c’ value of this parabola? (also known as the y
intercept?)_____
What does that mean???? ________
______________________________
How high was the baseball when it was first thrown?_______
When does the baseball approach 80 meters for the first time?
______
When does it approach the 80-meter mark again? _____
How much time has passed between these two points?_____
Therefore, which is the correct answer?____
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Look at the equation. The “c’ value is the
y intercept. You write that ( , ).
Eliminate ____ and ______
An x intercept always begins with a
number. That eliminates _____
Answer?______
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Does domain refer to the x-values or the yvalues?_____
What is the smallest x-value on the graph?____
Is this value actually included in the
domain?____ Why or why not?
________________________
What is the largest x-value on the graph?____ Is
this value actually included in the domain?____
Why or why not? ______________________
Now, which would be the range if the x were
changed to “y’?_________________
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Answer the same questions for this problem
as the last one.
Smallest x_______ Largest x_________
Now, what is the range is x was changed to
“y”?____________
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Simplification the easy way…use your
calculator
Put the problem at y1 and an answer at
y2. look at the table. If the y columns
are the same…you won.
Using Math:
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Using math:
But this one has a and b in it. Okay, make a = 2 and b
= 3 and simplify to an number answer..
Then use a=2 and b= 3 in the answers and see which
gets you the same answer.
Numbers first:
(__ *___) /___ =____
Eliminate ___ and ___
Now do your exponents.
Just doing “a’ will get
your answer.
Why?_____
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Quadratics For TAKS Three Methods on this page
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(2x +3) (5x -9) (multiply)
2x1 + 3
Times 5x1 - 9
-18x -27
10 x2 +15x
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10x2 -3x -27
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Do this like an old fashioned multiplication
problem
Multiply -9 times 3 = 27
Multiply -9 times 2x = 18x
Multiply 5x times 3 = 15x
Multiply 5x times 2x = 10x2 .
Add -18x and +15x = -3x
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TAKS TIP
Put the problem in the calculator at Y1
Put an answer at Y2
Press 2nd graph of table. If ALL the y
values match…it is correct.
• Or FOIL
• 10x2 -18x _+15x _-27__
• F
O
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• First Outside Inside Last
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-3x__
OI
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Combine Outside and inside
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Answer: 10x2 -3x - 27
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( 2x + 3 ) (5x -9)
First 2x * 5x = 10x 3rd
Outside 2x * -9 = -18x
Inside 3 * 5x = 15x
Last 3 * -9 = -27
Combine Outside and Inside
-18 x + 15x = -3x
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Quadratics
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Draw it:
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Formula for Area:________
Length = ___________
Width = _____________
Pick a method from page QQ1___
Find the answer. Show work.
Formula for area:____________
Length______________
Width______________
Use a different method from problem number
one. Show work
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Y = method?????
First, circle the zeros
and state them here:
x =____ and x = __
Three Ways:
1. Foil each answer, get an equation and graph it.
(yuk…lots of work)
2. Enter each answer as is on the calculator and
graph…easy
In both, look at the graph….If that does not help,
look at the table for the x values where y = 0.
3. Set each factor = to zero and solve. Those
should be your x values.
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Change to
decimals
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Tough one. Any ideas????
First graph it. Does it look like it is
symmetrical around the y axis???
Would a and b be symmetrical? _____
How about arithmetic? For c and d…plug
them in…which one works for both
answers?
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Graph it. Or substitute the answers in.
Just do it.
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