Suppose that you have $114 for tickets, and you want 6 tickets in the upper box section for weekday and weekend games. A ticket for the weekday is $18 and the weekend is $21. How many of each ticket can you buy?
I got the answer, x=4 y=2, but I don't know how to show my work
Let x = number of $18 ticket Let y = number of $21 ticket x + y = 6 the total number of tickets is 6 18x + 21y = 114 18x is the cost of x $18-tickets; 21y is the cost of y $21-tickets; 18x + 21y is the total spent = 114 x + y = 6 18x + 21y = 114 Solve the system of equations.
y=2 x=4
You already had written you knew the answer. Do you know how to solve the system of equations, or do you need help with it?
I need help with solving the system of equations (showing my work)
I've gotten to the step 18(6-y)+21y=114... after that I am stuck
Ok x + y = 6 18x + 21y = 114 Let's solve the system of equations using the substitution method. In this method, you first solve one equation for one variable. Oh, I see, you're getting there. x = 6 - y 18(6 - y) + 21y = 114 This is exactly what you have so far.
Now distribute the 18
108-18y+21y=114
18(6) - 18(y) + 21y = 114
Right
Now combine like terms on the left side
108-39y=114 ?
Careful with that addition. -18y + 21y You are adding two quantities with different signs, -18y and 21y
ohhhhhhh okkk! Thank you for catching that!!! 108+3y=114
and then -108 from both sides ???
3y=6/3 y=2!
The rule is take absolute values of the numbers: |21| = 21 |-18| = 18 Then subtract the smaller one from the larger one: 21 - 18 = 3 Then the sign is the same sign as the number that has the larger absolute value. 21 has a larger abs value than -18, and 21 is positive, so the answer is positive. so -18 + 21 = +3
Thanks!
3y = 6 y = 2. Correct. Now substitute y = 2 into one of the original equations to get x.
x=4
x + 2 = 6 x = 4 Correct. Answer is: 4 $18 tickets and 2 $21 tickets. Notice there is no x and y in the answer above. That is because the question does not use any x and y. We used x and y to represent the question mathematically. The person asking the question wants to know the numbers of tickets and has no idea what x and y are.
ahh right. Your attention to detail saved me! haha thanks so much!
You're welcome.
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