- Sailing A sailboat begins a voyage w ith 145 lb of food. The crew plans to eat a total
of 15 lb of food p er day.
a. W rite a n equ atio n in slope-intercept form relating th e rem aining food supply y
to the n u m b e r of days x.
b. Graph your equation.
c. The crew plans to have 25 lb of food rem aining w h e n they e n d th eir voyage. How
m any days does th e crew expect th eir voyage to last?
SAT/ACTSt a n d a r d i ze d Test Pr ep
- W hich e quation represents th e line th a t h as slope 5 a n d passes thro u g h th e
point ( 0 , - 2 )?
(X ) y = x - 2 C D y= 5x-2 CD y = ~ 2 x - 5 CD) y - 5x
Short. R e s p o n s e
64. W hat is th e slope of th e line th at passes thro u g h th e points ( - 5 , 3) an d (1, 7)?
5 ^ 2 2
CD 3 (C C (^33)
- W hich n u m b e r line shows th e solution of 12x + 5 1 < 3?
CD|Ca) « i • i—i • i i— i— i— i—n
—5 —4 —3 —2 —1 012345CD H—0 —H— —I— I— I— I— I— I-- 5 —4 —3 —2 —1 012345
+-•- H— I— I— h
—5 —4 —3 —2 - 1 012345
-•—i—I—I—I—I—I-
5—4—3—2—1 012345- W hich eq u a tio n represents th e graph at th e right?
CD y = ~ 2 X + 4
CD y = - 4 x + 1
CD y = - f x + 4
CD y = 4 x - \- If a, b, and c are real n um bers, a + 0, and b > c, is th e statem en t
ab > ac always, sometimes, or never t r u e? E x p l a i n.
Mixed Review
Suppose y varies directly with x. Write a direct variation equation that relates
x andy. Then find the value ofy when x = 10.^ See Lesson 5-2.68. y = 5 w h en x = 1. 69. y = 8 w h e n x = 4.Solve each equation. Justify each step.- y = 9 w h en x = 3.
See Lesson 2-2.- 21 = - 2 1 + 3 72. y - 3 = 6 73. 8 x + 5 = 61
Get Read y! To p r e p a r e fo r Lesson 5 - 4 , d o Exercises 7 4 - 7 7.
Simplify each expression.- —3(x - 5) 75. 5(x + 2) 76. -kx-6)
See Lesson 1-7.- 1.5(x+ 12)
314 Chapters Linear Funct ions