Answer:
Step-by-step explanation:
Since the expressions are multiplied, for the product to equal zero, one term or another has to equal 0 because 0 times anything is zero.
(10-x)(3x-9)=0 when
10-x=0, x=10
3x-9=0, x=9/3=3
So there are two solutions when x=3 and x=10
