Trapezoid help

[Andykinn]

Hi could someone help me, I am trying to work out if I want to increase the the size of a isosceles trapezoid by one cm all around, how do I calculate the extra length across the top, the shorter parallel line, for example if i trying to calculate the extra width from the center it is obviously more than one cm if the non parallel line is pushing out 1cm.
Hope that makes sense, searched the internet and cant find the answer

 

[Dr.Peterson]

I'm not sure what you want to do.

Apparently "increase the the size of a isosceles trapezoid by one cm all around" doesn't just mean to add 1 to the length of each of the four sides. So what does it mean? Is the result supposed to be similar to the original, for example?

Maybe sketch a picture and label the original trapezoid and the goal.

 

[Steven G]

Might you mean that you want to increase just three sides on the isosceles triangle by 1cm and want to know what the length of the longest parallel side should be? If yes, then please post that problem.