Assignment 8 

#$&*

course Mth163

Question: `q001. Note that this assignment has 5 questions

For the function y = 1.1 x + .8, what are the coordinates of the x = 2 and x = 9 points? What is the rise between these points and what is the run between these points? What therefore is the slope between these points?

YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY

Your solution:

When x=2 we get y= 1.1(2) + .8

Y= 2.2+ .8

Y= 3

So the coordinates for x=2 is (2, 3)

When x=9 we get y= 1.1(9) + .8

Y= 9.9 + .8

Y=10.7

So the coordinates for x=9 is (9, 10.7)

The rise is 10.7 - 3 = 7.7

The run is 9 - 2 = 7

So the slope is 7.7 / 7 or 1.1

confidence rating #$&*:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.............................................

Given Solution:

Evaluating y = 1.1 x +.8 for x = 2 and x = 9 we obtain y = 3 and y = 10.7. The graph points are therefore (2,3) and (9,10.7).

The rise between these points is 10.7 - 3 = 7.7 and the run is 9-2 = 7. Thus the slope is 7.7 / 7 = 1.1.

&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&

Self-critique (if necessary):

------------------------------------------------

Self-critique rating:

*********************************************

Question: `q002. For the function y = 1.1 x + .8, what are the coordinates of the x = a point, in terms of the symbol a? What are the coordinates of the x = b point, in terms of the symbol b?

YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY

Your solution:

When x= a we get y=1.1(a) + .8

When x= b we get y=1.1(b) + .8

So the coordinates for x=a are ( a, 1.1a + .8)

The coordinates for x=b are (b, 1.1b+.8)

confidence rating #$&*:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.............................................

Given Solution:

If x = a, then y = 1.1 x + .8 gives us y = 1.1 a + .8.

If x = b, then y = 1.1 x + .8 gives us y = 1.1 b + .8. Thus the coordinates of the x = a point are (a, 1.1 a + .8) and (b, 1.1 b + .8).

&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&

Self-critique (if necessary):

------------------------------------------------

Self-critique rating:

*********************************************

Question: `q003. We see that the coordinates of the x = a point are (a, 1.1 a + .8) and (b, 1.1 b + .8). What therefore is the rise between these two points? What is the run between these two points?

YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY

Your solution:

The rise is (1.1b+.8) - (1.1a+.8)= 1.1b - 1.1a

The run is b-a = b-a

confidence rating #$&*:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.............................................

Given Solution:

The rise between the points is the rise from y = 1.1 a + .8 to y = 1.1 b + .8, a rise of

rise = (1.1 b + .8) -(1.1 a + .8) = 1.1 b + .8 - 1.1 a - .8 = 1.1 b - 1.1 a.

The run is from x = a to x = b, a run of

run = b - a.

&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&

Self-critique (if necessary):

------------------------------------------------

Self-critique rating:

*********************************************

Question: `q004. We see that the rise between the x = a and x = b points of the graph of y = 1.1x +.8 is 1.1 b + .8 - (1.1 a + .8), while the run is b - a. What therefore is the average slope of the graph between these points? Simplify your answer.

YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY

Your solution:

The slope is 1.1b - 1.1a / b-a =

1.1(b-a) / b-a ; b-a cancel out

slope = 1.1

confidence rating #$&*:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.............................................

Given Solution:

The slope is

slope = rise / run = (1.1 b - 1.1 a) / (b - a) = 1.1 (b - a) / (b - a) = 1.1.

The significance of this series of exercises is that the slope between any two points of the straight line y = 1.1 x + .8 must be 1.1, no matter whether the points are given by numbers (e.g., x = 2 and x = 9) or by symbols (x = a and x = b). Mostly

&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&

Self-critique (if necessary):

------------------------------------------------

Self-critique rating:

*********************************************

Question: `q005. What are the rise, run and slope of the graph of the function

y = 3/2 x + 12

between x = 2 and x = 4?

In terms of the symbols a and b, what are the rise, run and slope of the graph of the same function between x = a and x = b?

YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY

Your solution:

When x=2 we get y= 3/2(2) + 12

Y=3+12

Y=15

(2, 15)

When x=4 we get y= 3/2(4) + 12

Y= 6+12

Y=18

(4, 18)

The rise is 18 - 15 = 3

The run is 4-2 = 2

The slope is 3/2 or 1.5

When x=a we get y= 3/2(a) + 12

(a, 3/2a + 12)

When x=b we get y= 3/2(b) + 12

(b, 3/2b + 12)

The rise is 3/2b+12 - 3/2a + 12 = 3/2b - 3/2a

The run is b-a = b-a

The slope is (3/2b - 3/2a) / b-a = 3/2 (b-a) / b-a = 3/2 = 1.5

confidence rating #$&*:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

------------------------------------------------

Self-critique rating:

"

Self-critique (if necessary):

------------------------------------------------

Self-critique rating:

"

Self-critique (if necessary):

------------------------------------------------

Self-critique rating:

#*&!

&#This looks good. Let me know if you have any questions. &#