1. calcium carbonate < calcium oxide + carbon dioxide

dr. Bob

Hydrolic acide + sodium hydroxide < sodium chloride + water

this cant be balanced already as assignment says we must balance each one

3 answers

CaCO3 ==> CaO + CO2
already balanced.

HCl + NaOH ==> NaCl + H2O
already balanced.

Your arrow is pointing the wrong way, I assume. If not, then reverse the equations I wrote. ALSO, the equations are balanced without adding coefficients other than 1 to each reactant and each product. So if you must place a coefficient for each, place a 1.
You are right the arrow on the 2 is the wrong way so I am so confused as to how to balance these 2 they are the last problems I have.
What do you not understand about the balancing? These are relatively easy ones to do. If you don't understand these, a more complicated one will give you real trouble. I can go through one to show you how to do it. It's just trial and error. But it helps to use a little logic with it.