Download Algebra 1 Unit 5.1 Post

Algebra 1 Unit 5.1 Post-test Review KEY
1. Write the equation for the following graphs in slope-intercept form.
y
–9 –8 –7 –6 –5 –4 –3 –2 –1
–1
–2
–3
–4
–5
–6
–7
–8
–9
y
y
9
8
7
6
5
4
3
2
1
9
8
7
6
5
4
3
2
1
9
8
7
6
5
4
3
2
1
1 2 3 4 5 6 7 8 9 x
–9 –8 –7 –6 –5 –4 –3 –2 –1
–1
–2
–3
–4
–5
–6
–7
–8
–9
𝒚 = −𝒙 − 𝟏
1 2 3 4 5 6 7 8 9 x
–9 –8 –7 –6 –5 –4 –3 –2 –1
–1
–2
–3
–4
–5
–6
–7
–8
–9
𝒙=𝟓
1 2 3 4 5 6 7 8 9 x
𝒚 = 𝟑𝒙 + 𝟓
Given the following functions find each value.
𝑓(𝑥) = −𝑥 2 + 4
2
𝑘(𝑥) = −𝑥 2 − 4𝑥 − 2
ℎ(𝑥) = (𝑥 − 2)(3𝑥 + 1)
𝑔(𝑥) = 3 𝑥 − 9
2. 𝑔(−3)
3. 𝑘(−3)
-11
1
4. 𝑓(−4)
-12
Now find x for each of the following using 𝑓(𝑥), 𝑔(𝑥)𝑎𝑛𝑑 ℎ(𝑥)𝑎𝑛𝑑 𝑘(𝑥)𝑎𝑏𝑜𝑣𝑒.
5. 𝑓(𝑥) = −5
3
6. 𝑔(𝑥) = 5
and -3
7. ℎ(𝑥) = 0
21
2 and -1/3
8. Graph the equations described below.
a) An equation parallel to 𝑦 = 𝑥 − 2
Explain how you know where to graph equation.
The slope is 1 so graph any line with a positive
y
slope of 1
9
8
7
6
5
4
3
2
1
–9 –8 –7 –6 –5 –4 –3 –2 –1
–1
–2
–3
–4
–5
–6
–7
–8
–9
2013-2014
b) An equation perpendicular to 𝑦 = −2𝑥 − 2
How do you know where to graph the equation?
Slope is -2 so perpendicular line would have
y
slope of ½. Start anywhere
on y axis, go up 1
9
8
and right 2.
7
6
5
4
3
2
1
1 2 3 4 5 6 7 8 9 x
–9 –8 –7 –6 –5 –4 –3 –2 –1
–1
–2
–3
–4
–5
–6
–7
–8
–9
1 2 3 4 5 6 7 8 9 x
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Algebra 1 Unit 5.1 Post-test Review KEY
8.Continued
c) An equation parallel to x =5
d) An equation with a slope of zero
y
y
9
8
7
6
5
4
3
2
1
–9 –8 –7 –6 –5 –4 –3 –2 –1
–1
–2
–3
–4
–5
–6
–7
–8
–9
9
8
7
6
5
4
3
2
1
Any vertical
line
Any
horizontal
line
1 2 3 4 5 6 7 8 9 x
–9 –8 –7 –6 –5 –4 –3 –2 –1
–1
–2
–3
–4
–5
–6
–7
–8
–9
1 2 3 4 5 6 7 8 9 x
9. Write an equation in slope intercept form for the following lines.
a) Slope is 7 and the y intercept is -2.
b) line goes through (5,9) and (-33,9)
y=9
𝒚 = 𝟕𝒙 − 𝟐
d) Perpendicular to 𝑦 = −5𝑥 − 2 and
through (0,4)
c) Slope is undefined and line goes through (5,7)
x =5
y=
e) Line goes through (0,-3) and (2,9)
f) Perpendicular to 𝑦 =
4
7
𝟏
𝟓
x+4
+ 2 and through (0,1)
𝟕
𝒚 = 𝟔𝒙 − 𝟑
𝒚 = −𝟒𝒙 + 𝟏
Use the table at the right to answer the following (express answer in function notation).
a. Find 𝑟(−𝑤). (1 pt)
𝒓(−𝒘) = −𝟐. 𝟓
3
b. Solve 𝑟(𝑥) = 2. (2 pts)
𝒓(−𝒕) =
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3
2
x
r(x)
-w
-2.5
-t
3
2
0
-5
t
6.2
w
-3
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