CP ALG II 9/1/15
Efficient Equations of Lines
Working efficiently with the three main forms of the equation of a line
makes us stronger!
SLOPE-INTERCEPT y = mx + b
STANDARD
y - y1 = m( x - x1)
POINT-SLOPE
Ax + By = C
Find the equation of the line. Answer in STANDARD form.
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Ex#1: through 0, 5 with slope 3.
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Ex#2: through 0, 5 and -2, -1 .
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Ex#3: through 0, 5 and -3, 0 .
Ex#4: through 1, 5 and -3, 0 .
Ex#5:
Ex#6:
CP ALG II 9/1/15
Efficient Equations of Lines
Graph each line. Be efficient!
Ex#7:
y = 3x - 5
Ex#8:
y - 3 = -2( x -1)
Ex#9:
2x - 3y = 6
Ex#10:
2y = -x + 8
CP ALG II 9/1/15
Efficient Equations of Lines
Ex#11:
a)
Find the equation of CD.
b)
Find the equation of BD.
c)
Find the equation of the line that passes through D and is PERPENDICULAR to AC.
d)
How is the line in question (c) related to AB? How do you know?
CP ALG II 9/1/15
Efficient Equations of Lines
FUNCTION NOTATION:
()
EX: Given f x = x 2 +3x -5, evaluate
()
a.
f 2
b.
f 0
c.
f -3
d.
f 2x
e.
f x +2
()
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