Andrew D. answered • 09/15/14

Tutor

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(1)
Computer Tutor & Math Empath

for this one, we need to assign either jack or lucy to a variable

since jack is 2 times older than lucy it is easier math to assign lucy to a variable.

so we say

lucy = x

now we set up our equation

if we know that 6 years ago their ages were 18 combined, then we know that something - 6 = 18

since we also know that jack is 2 times lucy now

then the entire formula would be

2x - 6 = 18

to solve we add 6 to both sides

2x - 6 + 6 = 18 + 6

the 6s on the left cancel because when you have a positive and negative of the same number it always = 0

we get

2x = 24

then divide both sides by 2 to get the answer

2x / 2 = 24 / 2

the 2s on the left cancel and you get

x = 12

then answer is 12

Sandra H.

So Lacey is 10 and Jack is 20 now.

Six years ago: Lacey is 10-6=4; Jack is 20-6=14; Total is 18

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11/18/14

Sandra H.

11/18/14