a) Joelle has y = 4x + 18 (She currently has 18 rocks and gains 4 each week)
b) Lewis has y = 3x + 30 (He currently has 30 rocks and gains 3 each week)
c) To find when they will have the same number of rocks, we set the equations equal to each other: 4x + 18 = 3x + 30
Subtract 3x from both sides: x + 18 = 30
Subtract 18 from both sides: x = 12
So, after 12 weeks, Joelle and Lewis will have the same number of rocks.
d) To find the number of rocks they will each have at that time, we substitute x = 12 into either equation:
Joelle: y = 4 * 12 + 18 = 48 + 18 = 66 rocks
Lewis: y = 3 * 12 + 30 = 36 + 30 = 66 rocks
So, when they have the same number of rocks in their collection, they will each have 66 rocks.
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)
a) 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?
_ weeks
d) How many rocks will Joelle and Lewis have when the amount of rocks in their collection is equal? They will each have _ rocks in their collection.
Word bank:
3
65
66
30
2
70
12
4
18
1 answer