Question

PLEASE HELP!!!!

1.   Find the correct table of values for the following function:  y = x – 3  (1 point)

x
y
10
8
8
6
6
4

x
 y
10
 13
8
 11
6
9

x
y
10
7
8
5
6
3

x
y
10
3
8
3
6
3



2.   Evaluate the function for x = 2: f(x) = 7x – 5  (1 point)

9

19

–9

–19



3.   Candy is on sale for $0.75 each. You have a coupon for $0.25 off your total purchase. Write a function rule for the cost of n pieces of candy.  (1 point)

C(n) = 0.25n – 0.75

C(n) = 0.75n – 0.25

C(n) = 1.0n

C(n) = 0.75n



4.   The ordered pairs (0, 0), (2, 4), (4, 8), and (6, 12) represent a function. What is the rule for this function?  (1 point)

y = x +2

y = 3x

y = x + 4

y = 2x

Answer 1

1. 3rd one

2. f(x) = 7x - 5
    f(2) = 7(2) - 5
    f(2) = 14 - 5
    f(2) = 9

3. c(n) = 0.75n - 0.25

4. (0,0)(2,4)
    slope = (4 - 0) / (2 - 0) = 4/2 = 2
    answer is : y = 2x

Answer 2

QUESTION 1

$y = x - 3$

When

x=10, y=10-3=7

$x=10, y=10-3=7 \\  \\ x=8, y=8-3=5 \\  \\ x=6, y=6-3=7$

Hence the correct answer is C.

QUESTION 2

We have

$f(x) = 7x - 5$

To evaluate this function at

$x = 2$

We replace x with 2 in the given function to obtain,

$f(x) = 7(2)- 5$

We now simplify to obtain,

$f(x) = 14 - 5 = 9$

The correct answer is A.

QUESTION 3

If each candy is $0.75, then n pieces will be

$ $0.75n$

If you have $0.25 off, then cost of n pieces of candy will be

$ $c(n)= 0.75n - 0.25$

The correct answer is B.

QUESTION 4

We have been given the ordered pairs,

$(0,0),(2,4),(4,8),(6,12)$

By inspection you can observe that,

$x \rightarrow2(x)$

Hence

$y = 2x$

Or we can alternatively use,

$y = mx + c$

and substitute any two points to find the constants.

When we substitute

$(0,0)$

We get

$0 = m(0) + c$

$0 = 0 + c$

which gives

$c = 0$

Our equation now becomes,

$y = mx$

We now substitute our second point, say

$(2,4)$

$\Rightarrow 4 = 2m$

$\Rightarrow 2= m$

Therefore,

The equation is

$y =2x$

Therefore the correct answer is D.