X - y = -2
7x + 2y = -5
Solve using substitution method

Step-by-step explanation:

x=-2+y

7(-2+y)+2y=-5

-14+7y+2y=-5

9y=9

y=1

x=-2+1

x=-1

es una operación aritmética.

step-by-step explanation:

no se que fórmula requiera, pero te puedo decir que es adición. deberías revisar porque tema vas y ver que fórmulas puedes aplicar.

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.