Bus A and Bus B leave the bus depot at 9 am. Bus A takes 30 minutes to complete its route once and bus B takes 40 minutes to complete its route once. If both buses continue to repeat their route, at what time will they be back at the bus depot together?

11 am

Step-by-step explanation:

Bus A and Bus B leave the bus depot at 9 am.

Bus A takes 30 minutes to complete its route once

Bus B takes 40 minutes to complete its route once.

We solve this finding the Lowest Common Multiple of the minutes each bus uses to complete it's route

30 = 3 × 10

40 = 4 × 10

= 3 × 4 × 10

= 120 minutes

120 minutes after 9 am is

60 minutes = 1 hour

60 minutes = 1 hour

= 2 hours.

9am + 2 hours

= 11 am.

Therefore, they be back at the bus depot together at 11 am

he used the algebra tiles correctly.

step-by-step explanation:

given : 3x(2x-1)

solution :

since he used algebra tiles .

armando's solution is the same in the solution shown in figure

as he distributed 2x into x and x and wrote them vertically

and also write   -1 vertically

and 3x into x and x and x and wrote it horizontally

performing the multiplication in the algebra tiles we get

and solving the given expression :

3x(2x-1)

since solving the expression using tiles   and solving the expression algebraically we get the same answer

thus   we can choose the first statement as the answer to this problem which is "he used the algebra tiles correctly".

step-by-step explanation:

x^2 -12x + 36 + y^2 = 36

x^2 + y^2 = 12x

r^2 = 12rcos(theta)

r = 12 cos(theta)