In pair annihilation, an electron and a positron destroy each other to produce gamma radiations. How is the momentum conserved?

Hint: The momentum of the final product is equal to the momentum of the initial elements.
In pair annihilation, an electron and a positron destroy each other to produce 2γ photons which move in opposite directions to conserve linear momentum. The annihilation is shown below 0e-1+0e+12γ ray photons.