Sally bought six pencils and three folders for $3.90. Henry bought two pencils and five folders for $3.30. Which system of equations can be used to find the price in dollars of each pencil, x, and each folder, y.

The pencils cost $0.4 each and the folders $0.5.

Step-by-step explanation:

Since Sally bought six pencils and three folders for $3.9. We have the following expression:

6*penchils + 3*folders = 3.9

And since Henry bought two pencils and five folders for $3.3. We have the following expression:

2*pencils + 5*folders = 3.3

The system of equations is given by:

6*pencils + 3*folders = 3.9

2*pencils + 5*folders = 3.3

In order to solve it we will multiply the second equation by -3 and sum both equations:

6*pencils + 3*folders = 3.9

-6*pencils - 15*folders = -9.9

We have:

-12*folders = -6

folders = 0.5

2*pencils + 5*0.5 = 3.3

2*pencils + 2.5 = 3.3

2*pencils = 3.3 - 2.5

2*pencils = 0.8

pencils = 0.8/2 = 0.4

The pencils cost $0.4 each and the folders $0.5.

x=17

step-by-step explanation:

solve 3x-24=x+10

then that makes it 2x=34 because you subtract an x from both sides to get rid of the one on the right, and then you add 24 to both sides to get rid of the 24 on the left

divide by both sides by 2 to get your answer so that you can get your answer

the red lines denote the population of the bacteria after 35 hours. that would be 2,409.24. the y-intercept is the blue line which is 800 because that is the starting point. the equation used to make the graph is 800(1.032)^h, where h is the number of hours.

step-by-step explanation: