Question

Which of the following represents the area of a rectangle whose length is 3x+5 and whose width is x-2
A.3x^2-x-10
B.3x^2-10
C.3x^2+x-10
D.3x^2-11x-10

Answer 1

i thinks its B. but i have no idea???

Answer 2

Well area of a rectangle is Length times Width; so (3x+5)(x-2).
1.Use FOIL (First, outer, inner, last)
3x times x=
3x times -2=
5 times x=
5 times -2=

2. Combine like terms.

Answer 3

i don t understand how to get 3x times x or 3x times -2?

Answer 4

would it be 4x and -6x?

Answer 5

Well 3x times x is 3x^2, since x time x is x^2
3x times -2 is -6x :D

Answer 6

Remember, you're multiplying not adding.

Answer 7

so its 3x^2-6x+5x-10

Answer 8

after i combine it to 3x^2-x^2-10

Answer 9

?

Answer 10

Remember when you combine like terms it's adding, the only time you multiply is in FOIL for this equation.
So what is -6x+5x?

Answer 11

-x^2 ???

Answer 12

-x, because when you add you're not going to get a square.

Answer 13

so then 3x^2-x-10 correct??

Answer 14

Yes.

Answer 15

ok thanks alot for all of your help c: