As others have mentioned, the load will be distributed between the bolts. How they will be distributed is more complicated, but it is usually assumed to be an equal division between the bolts (in this case), as SolarMike mentioned. This assumption is made easier by the cold work explained by blacksmith37.
From an analytical standpoint, all that can be inferred is that the sum of the forces acting on the bolts must be equal to the applied force of 30 kN. This equality must be satisfied.
To see why, don't look at the bolts, but at the plate. It suffers the effects of three different forces: the applied 30 kN force at the bottom (let's call it $P$), and the reactions of each of the two bolts (let's call them $R_A$ and $R_B$). If the sum of all of these forces (let's call it $F$) were not zero
$$F = P + R_A + R_B \neq 0$$
then that would imply that there is a net force applied to the plate. And as we know from Newton's Second Law of Motion, force equals mass times acceleration. If there's a non-null net force applied to the plate, then that means that the plate will need to be accelerating!
Obviously, if the applied load is too large and the bolts snap, then the applied load will no longer be balanced, there will indeed be a net force applied to the plate, and the plate will indeed accelerate in the direction of the force.