# Algebra 1

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solve if x=student price and y =adult price and 2y + 5x=77 and 2y + 7x=95 what are the price for admission for both adult and child

• Algebra 1 -

if i have 550 students and there are 144 more boys than girls how many girls are in class

• Algebra 1 -

Connie, I answered this question for you on Tuesday
http://www.jiskha.com/display.cgi?id=1331674038

• Algebra 1 -

REINY, Thank you for your answer and the answer is obviously correct when you go back and do the multiplying ......however , I do not just want the answer, I desperately wish to understand from start to finish how you got the answer. I am sorry if I seem stupid, really , but how did you get 2x = 18 , x=9 where did the 18 come from? I am so confused. Thanks for your help!!!! connie

• Algebra 1 -

I thought I showed every step in the solution ....

line them up above each other:
2y + 7x = 95
2y + 5x = 77
now subtract them to get
0 + 2x = 18

(2y-2y=0 , 7x-5x = 2x, 95-77 = 18)

so 2x = 18
divide both sides by 2
2x/2 = 18/2
x = 9

sub that back into one of the original equations
2y + 5(9) = 77
2y + 45 = 77
subtract 45 from both sides
2y + 45 - 45 = 77 - 45
2y = 32
divide by 2
y = 16

so x = 9 and y = 16