Answer:
The sides are 24cm, 7cm, and 25cm
Step-by-step explanation:
3x+x-1+3x+1=56 <---- First we combine like terms (the 1's cancel out)
7x/7=56/7 <--- Divide by 7 to isolate the variable
x=8 <--- Now that we've solved for x we need to plug it back into each side
3(8)=24
(8)-1=7
3(8)+1=25
24+25+7=56 <---- Make sure it all adds up to 56
Hope this helps :)