write system of equations to find the cost of the notebook and the pencil

Question

laura bought a notebook and pencil for 4.50. the notebook cost twice the amount of the pencil. write a systems of equations to find the cost of the notebook and pencil

Answer 1

Hi Brianna,

Great question! Let's represent notebooks with "N" and pencils with "P". Here's how we would set up the problem:

N + P = 4.50

N = 2P

Given N is equal to twice P, we can substitute that directly into the first equation:

(2P) + P = 4.50

3P = 4.50

P = 1.50

Now that we have P, we can in turn substitute that into either equation. I'll do both here (because, hey, math is fun!):

N + (1.50) = 4.50

N = 3.00

Or....

N = 2(1.50)

N = 3.00

There you have it! Be sure to watch the video I recorded for you for details, and feel free to reach out to me via my Wyzant profile for anything else I can be of help with!

My best,

Kelsey P.