Mandy and Jordan each bought some of the same notebooks and the same three-ring binder. Mandy paid $5.85 for 3 notebooks and 1 binder. Jordan paid $4.65 for2 notebooks and 1 binder. What is the price of one of the notebooks?

1 notebook costs $3.45

let's turn this into 2 equations, n being notebook price, and b being binder price - >

mandy - > 3n + b = 5.85

jordan - > 2n + b = 4.65

we need to take one equation, simplify for b, and plug it into the other equation, let's take jordan's equation for this - >

b = 4.65 - 2n

plug it into mandy's equation

3n + (4.65 - 2n) = 5.85

simpify until you get n = 1.20

take this and plug it back into jordan's equation - >

2 (1.20) + b = 4.65

simplify until you get b = 2.25

plus this value into mnady's equation - >

3n + (2.25) = 5.85

simplify until you get that n = 2.25