Mathematics
11 Online
OpenStudy (anonymous):
Simplify the rational expression. State any excluded values.
x^2-36/42x-7x^2
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
It would be (x-6)(x+6) but idk where to go from there
OpenStudy (anonymous):
so you already knows what is x^2-36 (from the previous question)
with 42x-7x^2
you can do something .. like taking out 7x .. what will you have ?
OpenStudy (anonymous):
x - 2 / x^2 + 3x - 10
x^2 - 36 / 6 - x
x^2 - 36 / 42 x - 7x^2
OpenStudy (anonymous):
how do you take out 7x?
OpenStudy (anonymous):
42x-7x^2 = 7x ( 6 - x )
(you take 7x out and what inside ( ) is every term divided by 7x )
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
\[42x - 7x^2\] has some terms common to them
Can you notice it?
OpenStudy (anonymous):
the x
OpenStudy (anonymous):
That is true
OpenStudy (anonymous):
Consider 42 and 7
OpenStudy (anonymous):
Can one go into the other?
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
yes
OpenStudy (anonymous):
What is that?
OpenStudy (anonymous):
6
OpenStudy (anonymous):
So 7 can go to 42 6 times
OpenStudy (anonymous):
yes
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
remember x was also common to them
This makes it 7x
OpenStudy (anonymous):
\[\frac{ x^2-36 }{ 42x - 7x^2 } = \frac{ (x + 6)(x - 6) }{ 7x(6 - x) }\]
OpenStudy (anonymous):
Can you continue from here?
OpenStudy (anonymous):
\[\frac{ x^2-36 }{ 42x - 7x^2 } = \frac{ (x + 6)(x - 6) }{ (7x)(-1)(x - 6) }\]
OpenStudy (anonymous):
so the answer would be x-6/7x
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
is it
OpenStudy (anonymous):
\[\frac{ x + 6 }{ -7x }\]
OpenStudy (anonymous):
or \[\frac{ -x - 6 }{ 7x }\]
OpenStudy (anonymous):
ty