Real  Quiz 6 

Grades are available as of Test 1. Email your name and W number to nalexander@igc.org
answers:  a c a a c b c
4.4 
1.  Yo, for people between the ages of 10 and 70, inclusive, the target zone for aerobic exercise is given by the following system of inequalities in which a represents one's age and p is one's pulse rate. 

10 < a < 70

2a + 3p > 450

a + p < 190


Suppose a person is 40 years old  with pulse rate 125 in beats per minute. Is this person inside the target zone?

a   yes
b no
c nota
5.1
2.  What is the degree of this polynomial ? f(x) = x3  - 4x  + 1 . Answer: degree is 3. Thus,  answer below is nota. 
a  2
b  4
c 1
d  nota
3.  Using the Leading Coefficient Test, we can say the polynomial of the previous problem:
a   falls to the left, rises to the right
b   rises  to the left, falls to the right
c   rises  to the left, rises to the right
d   falls to the left, falls to the right
e  nota
4. What is f(0) of problem 2?
a     1
b    -5
c   - 3
d     4
e  nota
5. Subtract. (4x4y - 8x6y2 + 12x8y6)  -  (4x4y  +   8x6y2  + 11x8y6 )
a   - 8x4y  -   16x6y2  - 24x8y6
b   - 8x4y   -   24x8y6
c   - 16x6y2    +   x8y6
d  nota
5.2
6. Multiply.  (x - 4) (x - 8)
a  x2 + 4x  -  32
b  x2 - 12x  +   32
c  x2 - 4x  -  32
d  nota
7. Multiply.  7t2(3t12 - 7t3  + t)
a  21t14  -   49t6    +    7t2
b  21t24  -  49t6       +    7t3
c  21t14  -  49t5       +    7t3
d nota
written problems
8. Multiply. (m  - 10)(m + 10) =m2 - 100
5.3
9  Factor completely.    
Answer: 
x10y6  +  12x8y5   + x4y3   - 26x5y3   =
x4y3 (x6y3 + 12x4y2 + 1 - 26x). 
10.  Factor this.    5x3   +  4x2  +    20x  +   16 ?  Hint:  factor by grouping. 
Answer: x2(5x + 4) + 4(5x + 4) = (x2 + 4)(5x + 4)
11.  Factor.  4(x  -  3)  +   B(x  -  3)  = (x - 3)(4 + B)
12. Factor by grouping:   
5x4   -   4x3  -  10x  +   8  =  x3(5x  -  4) - 2(5x -  4) = (x3 -  2)(5x -  4)
13. Section 4.4. EC (Extra Credit)   Graph  x  <  4  on the x-y plane.