13. Find the zeros of the function f(x) = x3 – 2x2 – 19x + 20, and ) + describe the behavior of the graph at each zero. А The graph touches the x-axis at 4, and it crosses the x-axis at -1 and -5. B The graph touches the x-axis at В 4, -5, and 1. C The graph crosses the x-axis at 5, 1, and -4. D The graph touches the x-axis at -4, and it crosses the x-axis at 1 and 5.

Set

x

3

−

2

x

2

−

19

x

+

20

equal to

0

.

x

3

−

2

x

2

−

19

x

+

20

=

0

Solve for

x

.

Tap for more steps...

x

=

1

,

5

,

−

4

image of graph

Step-by-step explanation:

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.