Mystery!
Recursively explicit? Or explicitly recursive?
Linear Functions
Identifying linear equations and their relatives
Inequality Paradise
100

Simplify.

root  108

6sqrt3

100

Write an explicit formula given the recursive formula.

a_1 = -3, a_n = a_(n-1) -4

a_n = 1-4n

100

Susie begins fishing with 9 worms.  She uses 3 worms every 2 hours.  Write a linear function for f(x) where x is the number of worms used.  After how many hours will all the worms be gone?

f(x) = -3/2 x + 9; 6 hours

100

Convert the equation from standard form to slope-intercept form.

6x - 2y = -20

y = 3x + 10

100

-x < -3

Is the circle open or shaded?  Is the line of solutions pointing left or right?

Open; right

200

Simplify:

-2sqrt112 

-8sqrt7

200

Write an recursive formula given the explicit formula, and identify the first term.

a_n = 8 + 20n

a_1 = 28, a_n = a_(n-1) +20

200

Two points on a line are A(1, 2) and B(4, 1).  Write a linear function for f(x) to represent this line.  What is f(-9)?

f(x) = -1/3 x + 7/3; 16/3

200

Write an equation in standard form which passes through the points (4, 0) and (0, -2).

x - 2y = 4

200

Solve.

- 2x < 4 or 4x > 20

x > -2

300

Write the domain using set notation

y=-2x^2-1

negative infinity < x < positive infinity

300

Write an explicit formula given the arithmetic sequence.

a_n = a_(n-1) + 2.4; a_1 = -1

a_n = -3.4 + 2.4n

300

Bob is competing in a 10-mile race.  He runs at a constant speed of 5 miles per hour.  Write a linear function for f(x) where  x represents the number of hours to determine how many miles Bob has left to run.  How many hours will it take Bob to finish the race?

f(x) = -5x + 10; 2 hours

300

Name the coordinates of the point on each axis where the line crosses it.

-x + 4y = -20

(0, -5) and (20, 0)

300

Solve.


-3x > - 6 or 5x > -5

x < 2 or x > -1

400

Write the range using interval notation

y=-2x^2-1

(negative infinity, -1]

400

The cost to rent a bicycle is $26 for the first day, then $12 for each day thereafter.  Write an explicit formula, then determine the cost to rent the bicycle for 10 days.

a_n = 14 + 12n; $134

400

A gym membership costs $12 per month, but charges a one-time enrollment fee of $120.  Write a linear function f(m) where m represents the number of months to determine the total cost of your gym membership.  How much will you spend on your gym membership after the first year?  How much will you spend the second year? 

f(m) = 12m + 120; $264; $144

400

A line passes through the points A(n, 4) and B(6, 8) and is perpendicular to y = 2x + 5.  What is the value of n?

14

400

Solve.

-5 < -3x - 2 < 4

-2 < x < 1

500

What are the x-intercept and y-intercept?

y=-2x^2-1

y-intercept (0, -1)

x-intercept:  NONE

500

An online store charges $5 to ship one box and $10 to ship two boxes. Write an explicit formula for an arithmetic sequence to represent the amount the online store charges to ship n boxes. Then determine how much the online store charges when shipping 11 boxes.

a_n = 5n; $55

500

A local restaurant offers you your first job.  They start you at $14.70 per hour minimum wage since you have 0 years of experience.  Every year thereafter, your wages will increase $0.55.  Write a linear function f(x) where x is the number of years of experience to determine your wages.  How much will your wages be after 3 years of experience?


f(x) = .55x + 14.70; $16.35

500

Find the equation of a line perpendicular to the given line passing through the point (-20, 4).  

5x - 2y = 3

y = -2/5 x - 4

500

Solve. 

9x - 1/7 x - 2 > 17/7

x > 1/2