Afamily reunion of 27 decided to go to six flags magic mountain. adult tickets cost 40 each and child tickets cost 30 each. the total cost of all tickets was 930. use the substitution method to determine how many adults and how many child tickets were purchased?

X= # adult tickets purchased
y= # child tickets purchased

Add the number of adults and children to equal 27. Then you need a second equation to determine cost. Adult tickets are 40 each (40*each adult), tickets for children are 30 each (30*each ticket for children). Add those to equal total cost of 930.

x+y=27
40x+30y=930

Solve for one variable in equation one, then substitute the answer in equation two.

x+y=27
Subtract y from both sides
x=27-y

Substitute (27-y) for x in the second equation.

40x+30y=930
40(27-y)+30y=930
1080-40y+30y=930
1080-10y=930
Subtract 1080 from both sides
-10y= -150
Divide both sides by -10
y=15 # child tickets purchased

Substitute y=15 into either equation to solve for x.

x+y=27
x+15=27
Subtract 15 from both sides
x=12 # adult tickets purchased

Check work:
40x+30y=930
40(12)+30(15)= 930
480+450=930
930=930

Hope this helps! :)