John, Mark, and Sheila commute a total of 2 hours a day. John's commute is 0.5 of an hour longer than Mark's, and Sheila's commute is twice as long as Mark's. Let x represent the length of Mark's commute. Which expression represents the length of John's commute? Which expression represents the length of Sheila's commute?

John's commute = x + 0.5

Sheila's commute = 2x

Step-by-step explanation:

Given:

Total hour commute = 2

Mark's commute = x

John's commute = x + 0.5

Sheila's commute = 2x

Find:

Each commute

Computation:

Total hour commute = Mark's commute + John's commute + Sheila's commute

2 = x + x + 0.5 + 2x

4x = 1.5

x = 0.375  hour

John's commute = x + 0.5

John's commute = 0.375 + 0.5 = 0.875 hour

Sheila's commute = 2x

Sheila's commute = 2(0.375) = 0.75 hour

a4 - 3a2 - 1

step-by-step explanation:

step   1   :

equation at the end of step   1   :

  ((a4) -   3a2) -   1

step   2   :

trying to factor by splitting the middle term

2.1     factoring   a4-3a2-1  

the first term is,   a4   its coefficient is   1 .

the middle term is,   -3a2   its coefficient is   -3 .

the last term, "the constant", is   -1