Algebra 1 Common Core Student Edition, Grade 8-9

Pr act i ce an d Pr o b l em - So l v i n g Ex er ci ses

Practice

MATHEMATICAL

PRACTICES

Q Apply

Determine whether each table or rule represents a linear or an exponential

function. Explain why or why not.

4^ See Problem 1.

8.

a 11 2 3

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10. y = 4 • 5X


11. y = - 5 • 0.25x

Evaluate each function for the given value.

14. fix) = 6X for x = 2


15. y = 20 • 0.5X for x = 3
    11. y = 12 • x
    13. y= 7x+ 3


16. g(f) = 2 • 0.4f for t = —2


17. h{w) = —0.5 • 4w for w = 18

4* See Problem 2.

18. Finance An investm ent of $5000 doubles in value every decade. I h e function
    j{ x) = 5000 • 2X, w here x is th e n u m b e r of decades, m odels the grow th of th e value
    of the investm ent. How m u ch is th e investm ent w orth after 30 yr?


19. W ildlife M anagem ent A p o p u latio n of 75 foxes in a wildlife preserve q uadruples
    in size every 15 yr. The function y = 75 • 4X, w here x is th e n u m b e r of 15-yr periods,
    m odels the p o pulation growth. How m any foxes will th ere be after 45 yr?

Graph each exponential function.

20. y=4x 21. y = —4X


21. y = 10 • ( | ) X 25. y = 0.1 • 2X

22.y= [lf

26. y = i * 2 x

See Problem 3.

a-r-tir

27. y = 1.25x


28. Admissions A n ew m u seu m h a d 7500 visitors this year. The m u se u m curators 4^ See Problem 4.
    expect th e n u m b e r of visitors to grow by 5% each year. The function
    y = 7500 • 1.05x m odels the p re d ic ted n u m b e r of visitors each year after xyears.
    Graph the function.


29. Environment A solid w aste disposal p lan proposes to reduce th e am o u n t of
    garbage each perso n throw s out by 2% each year. This year, each perso n threw out
    an average of 1500 lb of garbage. The function y = 1500 • 0.98x m odels th e average
    am o u n t of garbage each p erso n will throw o u t each year after xyears. Graph
    the function.
    1 What is the solution or solutions of each equation? See Problem 5.


30. 4X = | x + 5 31. x+3 = 3x

Evaluate each function over the domain { — 2, —1 , 0 , 1 , 2 , 3 }. As the values of the

domain increase, do the values of the range increase or decrease?

32. f{x) = 5X 33. y = 2.5X 34. h(x) = 0.1x 35. fix) = 5 • 4X


33. y = 0.5X 37. y = 8X 38. g(x) = 4 • 10x 39. y = 100 • 0.3X

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