Question 857833
X + 10 = 3(x-10)
x + 10 = 3X - 30
Subtract x from each side
10 = 2x - 30
Add 30 to each side
40 = 2x
Divide each side by 2
20 = x
.
Let's plug it in to prove.
In ten years (you'll be 30), your age will be 3* (20-10)
30 = 3*10
Success!