Question

use the distributive property to multiply.
10(c+d)

Answer 1

distributivity laws 1 & 2:

A,B vectors
a,b real numbers

1: (a+b)*A = a*A + b*A
2: a*(A+B) = a*A + a*B

So if c,d are vectors, 10*(c+d) = 10*c + 10*d