Hector entered a 3-day bike race. he traveled 20t miles on the first day, 15(t+6) miles the second day, and 25(t-3) miles the third day. which polynomial represents the average number of miles hector traveled each day? a. 20t+1 b.20t+5 c. 60t+3 d. 60t+15

The average number of miles he traveled each day is

Step-by-step explanation:

In order to calculate the average, we notice that it is a 3-day race, and we have the data of miles traveled each day. Mathematically we are saying that

where A is the average we want to calculate, so

therefore

is the average number of miles he traveled each day, wich is the polynomial b.

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.