Need ! the cost of three notebooks and four pencils is $7.20. the cost of five notebooks and eight pencils is $13.20. write a system of equations to model this situation. how much does one pencil and one notebook cost?

would also like steps, but that optinal

3n +4p = 7.20

5n+8p=13.20

pencil = $0.9

Notebook =$1.2

Step-by-step explanation:

Hi, to answer this question we have to analyze the information given:

The equation for this statement is:

3n +4p = 7.20 (a)

where:

n = cost of one notebook

p = cost of one pencil

5n+8p=13.20(b)

So, isolating n in (a)

3n +4p = 7.20

3n  = 7.20 -4p

n = (7.20 -4p)/3

n = 2.4 - 4/3 p

Replacing "n" in (b)

5n+8p=13.20

5 (2.4 - 4/3 p)+8p =13.20

12-20/3p +8p =13.20

-20/3 p +8p =13.20-12

4/3 p = 1.2

p = 1.2 / (4/3)

p= 0.9

Replacing "p" in(a)

3n +4p = 7.20

3n +4(0.9) = 7.20

3n +3.6 =7.20

3n =7.20-3.6

3n =3.6

n =3.6/3

n= 1.2