Question 497332
These side will be equal, since this is an equilateral traingle.
2x + 1 = 4x - 9 1/4 
10 1/4 = 2x
x = 5 1/8
2( 5 1/8 )  + 1 = 11 1/4 in
4( 5 1/8 ) - 9 1/4 = 20 1/2 - 9 1/4 = 11 1/4 in.
This does check.
The side is 11 1/4 inch and x is 5 1/8.
Cloemenius.