Question

At a concession stand, One person purchased 3 drinks and 3 soft pretzels. Another person purchased a total of $9.00. Another person purchased 4 drinks and 2 soft pretzels for a total of $8.50. What was the price of one soft pretzel?

Please help me understand how to do this question, My teacher didn't really help make sense of this.
The lesson is: Application of system

Answer 1

x=price of one drink.
y=price of one soft pretzel

We can suggest this system or equations:

3x+3y=9
4x+2y=8.5

We can solve this system of equations by substitution method.
3x+3y=9
3x=9-3y
x=9/3 - 3/3 y
x=3-y

4(3-y)+2y=8.5
12-4y+2y=8.5
-4y+2y=8.5-12
-2y=-3.5
y=-3.5/-2
y=1.75

x=3-y
x=3-1.75
x=1.25

Answer: The price of one soft pretzel is $1.75.

Answer 2

$1.75

Explanation:

Let x be the cost of 1 drink

Cost of 3 drinks = $3x

Cost of 4 drinks = $4x

Let y be the cost of 1 soft pretzels.

Cost of 3 soft pretzels=$3y

Cost of 2 soft pretzels=$2y

Now we are given that One person purchased 3 drinks and 3 soft pretzels. Another person purchased a total of $9.00.

So, equation becomes :
`3x+3y=9` --1

Now we are given that Another person purchased 4 drinks and 2 soft pretzels for a total of $8.50.

So, equation becomes :
`4x+2y=8.5`--2

Solving 1 and 2 graphically

Intersection point provides the answer of the system of equations

Refer the attached graph

Intersection point : (1.25,1.75)

Hence the price of one soft pretzel is $1.75