A breakfast menu liste 3 eggs with 2 sausage for $4.15 or 4 eggs with 1 sausage for $4.30 . What is the cost of 1 egg, and what is the cost for 1 sausage?

Cost of 1 egg = x = $0.89

Cost of 1 sausage = y = $0.74

Step-by-step explanation:

Let the:

Cost of 1 egg = x

Cost of 1 sausage = y

A breakfast menu lists:

3 eggs with 2 sausage for $4.15

3x + 2y = 4.15Equation 1

4 eggs with 1 sausage for $4.30 .

4x + y = 4.30 Equation 2

y = 4.30 - 4x

We substitute 4.30 - 4x for y in Equation 1

3x + 2(4.30 - 4x) = 4.15

3x + 8.6 - 8x = 4.15

3x - 8x = 4.15 - 8.6

-5x = -4.45

x = -4.45/-5

x = $0.89

Solving for y

y = 4.30 - 4x

y = 4.30 - 4(0.89)

y = 4.30 - 3.56

y = $0.74

Therefore,

Cost of 1 egg = x = $0.89

Cost of 1 sausage = y = $0.74

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m