Triangle and parallelogram in the space

Area of triangle formed by $\overline{a_1}=(3,1,2), \overline {b_1} = (3,-5,5)$ is equal to the area of the parallelogram formed by $\overline{a_2} = (4,7,3), \overline{b_2}=(4,6,x)$ . Let $y_1$ and $y_2$ are the possible values that satisfy $x$ . What is the value of $\lfloor y_1+y_2 \rfloor$ ?