This is called the Long Straddle, in such case there will be two Break Even Points, one at Upper level and one at Lower level, the formula to calculate will be like this Strike Price + Net Premium Paid for Upper BEP and Strike Price - Net Premium Paid for lower BEP.

calculation of breakeven is easy… You take a Strike Price and add net premium which will give you higher breakeven point and deduct net premium from Strike Price it will give you lower breakeven point.