Answer: The three sides are 14, 14, 20
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x = length of the two equal sides
x+6 = length of the third longer side
add up the three lengths x, x, x+6. Set it equal to the perimeter 48. Solve for x
x+x+x+6 = 48
3x+6 = 48
3x+6-6 = 48-6 ... subtract 6 from both sides
3x = 42
3x/3 = 42/3 ... divide both sides by 3
x = 14
If x = 14, then x+6 = 14+6 = 20
The three sides are 14, 14, 20
We can check this by adding up the three sides 14+14+20 = 28+20 = 48 and we get the right perimeter.
