Test 2: Word Problems and Linear Equations Test Review (HAND in PORTFOLIO)

Math 10F Name ______

Test 2: Word Problems and Linear Equations Test Review (HAND IN PORTFOLIO)

1. Rearrange these equations into y = mx + b form. Once you have done this, graph the line. (4 pts each)

1) 2x + y = 6 2) x – 2y = -10

Rearranged Equation: Rearranged Equation: m = b = m = b =

Graph: Graph

2) Use the following two equations to find the intersection point using the graphing method.

y  x  6 y  2x

Line 1: m = ______b = ______Line 2: m = ______b = ______

Intersection Point: ( , ) 3. A photographer charges a sitting fee of $15 and $5 for each photograph ordered. a) Show the relationship between the number of photographs ordered and the total cost in a table of values: (2 pts) Number of photographs Total cost ($) 0 1 2 3 4 5 b) How much does the pattern go up by each time? ______(0.5 pts) What does this represent? (slope or y-intercept?) ______(0.5 pts) c) What is the independent variable? ______(0.5 pt) What is the dependent variable? ______(0.5 pt) d) Draw a graph from your table of values. Label the axes and use an appropriate scale. (3 pts)

d) Using the graph, estimate the cost if you order 10 photographs. ______(1 pt) e) Write an equation in y = mx + b form. ______(2 pts) f) You order 40 photographs. How much did will you pay for these? Show all work. (Use the equation to find the answer.) (2 pts)

g) Your total cost was $150. How many photos did you order? Show all work. (Use the equation to find the answer.) (2 pts) 4. The temperature of a cup of warm water is 20°C. Every minute the water gets 2° colder. The graph is shown below:

a) Using the graph, estimate the temperature of the water after 20 minutes. ______(1 pt)

b) Using the graph,

estimate the number of

minutes it takes for the

temperature to be 10°.

______(1 pt)

c) Write an equation in y = mx + b form. (2 pt)

______

d) Use your equation to calculate the temperature of the water after 60 minutes. Show all work. (2 pt)

5. Complete the following table by indicating which is the independent variable and which is the dependent variable. (2 pts each)

Variables Independent Dependent Relationship/Correlation (positive, negative) The speed of a car and the number of speeding tickets you get The amount of income you earn and the number of years of education you have

6. For each graph, state the independent and dependent variable. (1 pt each)

Independent Variable: ______Independent Variable: ______Dependent Variable: ______Dependent Variable: ______7. You want to sell your car, so you’re going to put an ad in the paper. The cost to place an ad in two different newspapers is as follows:

Chronicle Herald: $16 initial charge, plus $2 per day Daily News: $10 initial charge, plus $4 per day a) Create an equation for each.

Chronicle Herald: ______Daily News: ______

Step 2: Solve using the comparison method for when the 2 options cost the same.

Intersection Point: ( , )

Step 3: What does this intersection point mean?

The graph is shown below:

If you need the add for only 2 days, which company should be hired? Write a sentence!

If the need the add for at least 7 days, which company should be hired? Write a sentence! 8. The scatter plot below compares the grade point average of students (ie, their marks) and the hours of video games they played.

a) Estimate the line of best fit. Use a ruler. (1 pt) b) What type of correlation is this? (strong or weak) ______(positive, negative, none) ______(1 pt) c) Complete the sentence below: As the grade point average increases, the number of video games… ______(1 pt) 9.

a) Draw a scatter plot from the data. Be sure to label the axes and use an appropriate scale. (4 pts)

d) Draw a line of best fit. Use a ruler. (1 pt) e) What type of correlation is this? (strong or weak) ______(positive, negative, none) ______(1 pt) f) Complete the sentence below: As the mass increases, the force… ______(1 pt) g) Predict the force needed when the mass is 4.5kg. Show your work on the graph. ______Is this interpolation or extrapolation? ______(2 pts) h) Predict the mass where there is a force of 22N. Show your work on the graph. ______(1 pt) Is this interpolation or extrapolation? ______(1 pt)