Question

What is the simplified form of x^2 - 16 over x +4 ?

x - 4, with the restriction x does not equal 4

x + 4, with the restriction x does not equal - 4

x + 4, with the restriction x does not equal 4

x - 4, with the restriction x does not equal - 4

Answer 1

Hint: use the difference of squares formula to factor the numerator x^2 - 16

Answer 2

i know its either a or d

Answer 3

good so far

Answer 4

the restriction is to avoid the denominator being zero

Answer 5

When you've solved using the difference of squares, you put that solution over x+4, and you cross out what you have on the top and the bottom that is the same. With what you hve left, that is your answer, but to find the restriction, you equal everything in the denominator to 0, which is in this case just one thing...that would be your restriction, or what x can not equal. :)

Answer 6

so what value of x makes the denominator x+4 equal to zero?

Answer 7

-4?

Answer 8

good, so that's your restriction (since it causes a division by zero error)

Answer 9

Thats what i dont really understand is the restriction

Answer 10

you cannot divide by zero

Answer 11

so if x+4 were zero, then x+4 = 0 ---> x = -4

so x = -4 makes the denominator zero, which is not allowed

Answer 12

so that's why that restriction is needed

Answer 13

so what would the restriction be?

Answer 14

just said it, -4

Answer 15

if x were -4, then you'd have a division by zero error

so that's why we restrict it

Answer 16

ohhh okay thank you ! (:

Answer 17

yw