SOLUTION: andy and brian together have $40, brian and chris have $62 and andy and chris have $58. how much money do the three of them have together ?
a $160 b $80 c $40 d $100
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-> SOLUTION: andy and brian together have $40, brian and chris have $62 and andy and chris have $58. how much money do the three of them have together ?
a $160 b $80 c $40 d $100
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Question 272223: andy and brian together have $40, brian and chris have $62 and andy and chris have $58. how much money do the three of them have together ?
a $160 b $80 c $40 d $100 e $120
use your first equation to solve for b in terms of a.
you get b = 40-a
use your third equation to solve for c in terms of a.
you get c = 58-a
substitute for b and c in your second equation to get:
b + c = 62 becomes:
40-a + 58-a = 62
combine like terms to get:
98 - 2a = 62
add 2a to both sides of this equation and subtract 62 from both sides of this equation to get:
98 - 62 = 2a
combine like terms to get:
36 = 2a
divide both sides of this equation by 2 to get:
18 = a
substitute for a in the first equation to get:
a + b = 40 becomes:
18 + b = 40
solve for b to get:
b = 40-18 = 22
substitute for a in the third equation to get:
a + c = 58 becomes:
18 + c = 58
solve for c to get:
c = 58-18 = 40
your solution should be:
a = 18
b = 22
c = 40
substitute in your original equations to see if these values are good.
