What is the product of the complex numbers (3 + i) and
(3 - i)?

\left(3+i\right)y\left(3-i\right)=10y

Step-by-step explanation:

\left(3+i\right)y\left(3-i\right)

\left(3+i\right)\left(3-i\right)y

=y\cdot \:10

=10y

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.