The vertex of the original equation has x-coordinate -b/(2a) = -(-10)/(2*1) = 5
so the axis of symmetry of the original equation is x=5.  So it must be
shifted 8 units left to go left to x=-3. We are given that it is shifted 3
units down and since the new value of "a" is to be 2 and not 1, it must also
be stretched by a factor of 2, otherwise "a" would remain 1.  So we replace
x by x-8, multiply the right side by 2 to stretch so that a=2, then subtract
3 to shift down 3 units, so the translated equation is



which simplifies to  



[However if we shift down 3 before we stretch to make a=2, the answer
will be 



which simplifies to  



Edwin