Question 834443
L + 10 = 3 (L - 6)
Distribute the L
L+10 = 3L - 18
Add 18 to each side
L + 28 = 3L
Subtract L from each side
28 = 2L
Divide by 2
14 = L
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Let's make sure it works.
10 years from now, Lisa will be (14+10=24) - is that 3 times the age she was 6 years ago? 6 years ago, she was 14-6=8.  8*3 = 24
Success!