Respuesta :

Answer:

3x+5

Step-by-step explanation:

The base has length 3x+5. You answered your own question darling

So 3x-1=2x+4
+1. +1
3x=2x+5
-2x -2x
X=5
To find the base it is
3x+5
So 3(5)+5
=15+5
=20
Hope it helps