Transcript Takayuki Ikkaku, Arisa Hosaka and Toshihiro Kawabata Objectives

Objectives:
Solve quadratic equations by finding
square roots.
Use quadratic models.
Give a man a fish, and he'll eat for a day. Give a fish a man, and he'll eat for
weeks!
Takayuki Ikkaku, Arisa Hosaka and Toshihiro Kawabata
Standard Form
Linear Equation
Ax + By = C
A quadratic equation can be written in the standard form;
ax2 + bx +c = 0
AX2 + BX +C = 0
a, b, and c are called?
a is the leading coefficient
coefficients
Quadratic equations are equations where the highest power of
the variable is 2.
Which equations are quadratic?
2.
3x2 + 2x + 5 = 0 yes
yes
5z2 + 5z = -3
3.
x2 = 2
yes
4.
y2 + y = y3
no
5.
4x + 2x = 0
6.
y=3
1.
no
no
How do we solve a quadratic of the form x2 = d?
x 9
2
x  9
x  3
2
1.
x2 = 4
2.
x2 = 5
3.
x2
4.
x2 = -1
=0
x=2
Two solutions
x =  √5 Two solutions
x=0
One solution
No solutions
Solve 3x2 -48 = 0
3x  48  0
2
3x  48
2
x  16
x  4
2
d = rt can be used to model problems with constant
speed.
The height of a falling object can be modeled using
h = -16t2 + s
where s is the height in feet from which the object
was dropped and t is the number of seconds it has
fallen.
If you were to drop a watermelon from the top of a
200 ft building, how long would it take to hit the
ground?
h = -16t2 + s
0=
-16t2
+ 200
height when hits the ground
-200 = -16t2
200 ft
12.5 = t2
√12.5 = t
3.54  t
starting height
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