(-64)x(-9)+64

I think you meant to say to find the value using suitable property. 
Here is the solution:
(-64) x (-9) + 64
={(-64) x (-9)} + 64
=-{64 x 9} + 64
= {64 x 9} + {64 x 1}
= 64 x (9 + 1)
= 64 x 10 
= 640

Answer = 640

Hope it helps!