Can someone help me with this please

The system of equations is

40x + 55y = 920

40x + 65y = 1000

x is the cost of the adult ticket; y is the cost of the child ticket

Step-by-step explanation:

If you have to solve this, elimination is a good method.

Subtract the top equation from the second equation.

40x + 65y = 1000

-40x + 55y = 920  x cancels  Solve for y

0  + 10y  =  80    Divide both sides by 10

y  = 8 .  Substitute 8 for y in either equation and solve for x

40x + 65(8) = 1000

40x + 520 = 1000   Subtract 520 from both sides

  40x = 1000 - 520

40x = 480   Divide both sides by 40

x = 12  

d

step-by-step explanation:

d

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.