Joelle currently has 18 rocks in her collection and gains 4 each week. Lewis currently has 30 rocks in his collection and gains 3 each week. Set up a system of equations to show how many rocks each has in their collection.(6 points)

) Joelle has y = x +

b) Lewis has y = x +

c) After how many weeks will Joelle and Lewis have the same number of rocks in their collections? Response area weeks

d) How many rocks will Joelle and Lewis have when the amount of rocks in their collection is equal? They will each have Response area rocks in their collection.

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1 answer

a) Joelle has y = 18 + 4x, where x is the number of weeks.
b) Lewis has y = 30 + 3x, where x is the number of weeks.
c) To find when they have the same number of rocks, we set the two equations equal to each other:
18 + 4x = 30 + 3x
x = 12
So, they will have the same number of rocks after 12 weeks.

d) To find out how many rocks they will have when the amount is equal, we substitute x = 12 into either equation:
Joelle: y = 18 + 4x = 18 + 4(12) = 18 + 48 = 66 rocks
Lewis: y = 30 + 3x = 30 + 3(12) = 30 + 36 = 66 rocks
Therefore, they will each have 66 rocks in their collection when the amount is equal.