Use a graphing calculator or other technology to answer the question. Which quadratic regression equation best fits the data set?

yˆ=32.86x2−379.14x

yˆ=32.86x2+379.14x−1354.14

yˆ=32.86x2−379.14x+1354.14

yˆ=−1354.14x2−379.14x+32.86

x y
3 455
4 401
5 388
6 211
7 299
8 323
9 678

answer: 1, 3 and 5 are correct

step-by-step explanation:

part a

x     y

0     8

1     7.5

2     7

3     6.5

4     6

5     5.5  

for every hour i deducted .5 inches from the length of the candle

part b

it is a function because for every x value there is only one y value

part   c

for every x value there is only one y value

x       y

0       8

1       7.6

2       7.2

3       6.8

step-by-step explanation:

answer: 414,377,008

step-by-step explanation:

just multiply it

the system of inequalities is

step-by-step explanation:

step 1

find the equation of the dashed line

we have the points

(0,0) and (3,1)

the line passes through the origin, so, is a direct variation

find the slope

the equation of the dashed line is

the solution of the inequality a s the shaded area above the dashed line

therefore

the equation of the inequality a is

step 2

find the equation of the solid line

we have the points

(4,0) and (0,4)

find the slope

the equation of the solid line is

the solution of the inequality b s the shaded area below the solid line

therefore

the equation of the inequality b is

step 3

the system of inequalities is