Name: _____________________
Class: _________________
AU10: Notes & HW – Lesson 4
Date: _________________
1. If the quadratic formula is used to find the roots of the equation x 2  6 x  19  0 , the correct
roots are (FS 2 – AU7)
(1) 3  2 7
(3) 3  4 14
(2)  3  2 7
(4)  3  4 14
2. Chelsea has $45 to spend at the fair. She spends $20 on admission and $15 on snacks. She
wants to play a game that costs $0.65 per game. Write an inequality to find the maximum
number of times, x, Chelsea can play the game. (RJu11#35 – AU1)
Using this inequality, determine the maximum number of times she can play the game.
3. Donna wants to make trail mix made up of almonds, walnuts and raisins. She wants to mix
one part almonds, two parts walnuts, and three parts raisins. Almonds cost $12 per pound,
walnuts cost $9 per pound, and raisins cost $5 per pound. (SS5 – AU1)
Donna has $15 to spend on the trail mix. Determine how many pounds of trail mix she can
make. [Only an algebraic solution can receive full credit.]
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4. The table below shows the relationship between the length of a person’s foot and the length of
his or her stride. (GC 5 – AU3/5)
Write the linear regression equation for this set of data, rounding all values to the nearest
hundredth.
Using the linear correlation coefficient, explain how accurate this function is in predicting a
person’s stride length.
Predict the stride length, in inches, of a person whose foot measures 8 inches.
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5. On the set of axes below, graph the function represented by y  3 x  2 for the domain
 6  x  10 . (FS 4 – AU2)
y
x
3
6. Use the data below to write the regression equation ( y  ax  b ) for the raw test score based
on the hours tutored. Round all values to the nearest hundredth. (FS 14 – AU5)
Equation: ____________________________________________________
Create a residual plot on the axes below, using the residual scores in the table above.
Based on the residual plot, state whether the equation is a good fit for the data.
Justify your answer.
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7. The figures below show the first four steps of making Sierpinski’s Triangle.
a. What fraction of each figure is shaded? (M3:EM#4 – AU6*)
b. Use your answer from part (a) to write a function rule which relates the step number to the
fraction of the figure that is shaded.
c. What fraction of step 6 would be shaded?
d. What fraction of each step is NOT shaded?
e. Write a function rule which relates the step number to the fraction which is NOT shaded.
f. What fraction of step 8 is not shaded?
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(M4:EM#2 – AU9)
8. Compare the following three functions:
i. A function f is represented by the graph below:
ii. A function g is represented by the following equation:
2
g x   x  6  36
iii. A linear function h is represented by the following table:
For each of the following, evaluate the three expressions given and identify which expression has
the largest value and which has the smallest value. Show your work.
a. f 0, g 0, h0
b.
f 4  f 2
42
g 4  g 2
42
h4  h2
42
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