SOLUTION: I need help on Expressions involving variables, substitution. "John paid $34 for two algebra and three geometry books. He paid $36 for three algebra and two geometry books. What

Question 564110: I need help on Expressions involving variables, substitution.
"John paid $34 for two algebra and three geometry books. He paid $36 for three algebra and two geometry books. What is the cost of each book?"
Thank You!

Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
Algebra book cost x
geometry book cost y
2x+3y=34
3y=-2x+34
y=(-2/3)x+34/3
3x+2y=36
substitute y in the equation
3x+2((-2/3)x+34/3)=36
3x-(4/3) x +68/3=36
multiply equation by 3
9x-4x+68=108
5x=40
x=8 , algebra book cost
plug x in equation 2x+3y=34 to get y=6

RELATED QUESTIONS
John paid $83 for one algebra and three geometry books. He paid $95 for three algebra and (answered by ewatrrr,richwmiller)

2 algebra books and 3 geometry books cost $ 34, and 2 algebra books and 2 geometry books... (answered by ikleyn)

i need to know the steps so that i may help my son under stand more clearly.The processof (answered by rapaljer)

How do i solve 3x-6y=30 and how do i solve y=-6x+34 using the expressions involving... (answered by stanbon)

Algebra: variables and... (answered by ReadingBoosters)

Need help with geometry and algebra? (answered by sofiyac)

How many different ways can three algebra books, two trigonometry books, and two... (answered by lynnlo)

Really, expressions involving variables, subtraction: I am trying to solve... (answered by rapaljer)

I need help. john and mary borrowed %600 at 12% simple interest for the period of three... (answered by rfer)