Respuesta :

8 x 45 = (8 * 40) + (8 * 5) ...now that can be done mentally
8(50-5) = 400 - 40 = 360
use compatible numbers.
you have to apply the distibtive poperty  
8 x 45.
leave the 8
split 45 into tow numbers that add up to 45
40 and 5.
multiply each number by 8
8 x 40 + 8 x 5.
320 + 40
when you add both it will be 360