February 11, 2015
Section P.5 Solving Equations Graphically,
Numerically, and Algebraically
Solving Equations Graphically
Solve x2 − 8x = -14 using your graphing
calculator.
Round all solutions to the nearest hundredth unless directed
otherwise. You must copy the graph into your notebook and
show the point(s) you found to be solution(s).
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February 11, 2015
Quadratic Equation in x:
ax2 + bx + c = 0, where a, b, and c are
real numbers with a ≠ 0.
The Zero Product Property
Let a and b be real numbers. If ab = 0,
then a = 0 or b = 0.
Methods of Solution for Quadratic Equations:
Factoring
Extracting Square Roots
x
Completing the Square
Quadratic Formula - What is it?
x=
-b ±
b2 - 4ac
2a
Solve 2x2 + 5x − 3 = 0 by factoring.
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February 11, 2015
Solve by extracting square roots.
Solve by completing the square.
Solve the quadratic formula.
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February 11, 2015
Solve graphically.
Graph each side of the equation and find the
intersection(s). How many are there?
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•
•
Solve the equation for zero and find the root(s).
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February 11, 2015
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February 11, 2015
A Norman window has the shape of a square with
a semicircle mounted on it. Find the width of the
window if the total area of the square and the
semicircle is to be 200 sq. ft.
Write a function for area in
terms of x.
x
x
Set the function equal to 200 and solve for x.
.
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