Question 174707: 1.Write the equation of a line with a slope of 2 if f(-1)=5.
2. For each equation describe the SHAPE of the graph:
a) x-2y=4
b) y=(x)(x)-4
c)y=the absolute value of x+4
d) y-2= -(x+2)
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! 1.Write the equation of a line with a slope of 2 if f(-1)=5.
f(-1) = 5 means that when x = -1, y = 5, so that's the point (-1,5).
Now the problem is to find the eqn of the line thru (-1,5) with a slope of m=2.
y - y1 = m*(x - x1) where (x1,y1) is the point (-1,5)
y-5 = 2*(x - (-1))
y-5 = 2x + 2
y = 2x + 7
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2. For each equation describe the SHAPE of the graph:
a) x-2y=4
It's a linear eqn, so the graph is a straight line. Put it into slope-intercept form: y = (1/2)x - 2 --> it has a slope of +1/2, and it crosses the y-axis at (0,-2).
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b) y=(x)(x)-4
Do you mean x^2 - 4? If so, it's a parabola symmetrical about the y-axis crossing the x-axis at (-2,0) and (2,0), and its vertex is at (0,-4).
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c)y=the absolute value of x+4
d) y-2= -(x+2)
y = -x
A straight line thru the origin with a slope of -1.
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