Question

please help
What does the product (-5 - 2i)(3 + 7i) equal?
A) -15 - 14i
B) -1 - 41i
C) -29 -41i
D) -1 + 41i
E) -29 + 41i

Answer 1

Just do regular distribution.
Remember that i^2=1.

Answer 2

multiply as follows:

(-5)(3) = -15
(-5)(7i) = -35i
(-2i)(3)= -6i
(-2i)(7i) = -14i^2

Answer 3

so you have

-15-35i-6i-14i^2

Answer 4

thats what i got. i see what i did wrong

Answer 5

Oops, I meant i^2=-1.
Sorry!

Answer 6

now combine like terms
so you have

-15 -41i -14i^2

Answer 7

now you substitute the i^2 = -1 like Alwayshte Booworm said

Answer 8

hold on afk

Answer 9

so you have

-15 -41i -14(-1)

-15 -41i+14

Answer 10

Multiply in this manner:

(-5 - 2i)(3 + 7i)
= -5(3 + 7i) -2i(3 + 7i)
= -15 -35i - 6i - 14i^2
= -15 -41i -14(-1)
= 14 - 15 - 41i
= -1 - 41i

Answer 11

so combine like terms and you have
-1-41i

Answer 12

thanks

Answer 13

yw :)