Answer:
9a-65
Step-by-step explanation:
simply write 9a+(add the remaining numbers all together)
Answer:
3ab
-------------------
(b+a)
Step-by-step explanation:
3/a - 3/b
-------------------
1/a^2 - 1/b^2
Multiply the top and bottom by a^2 b^2/ a^2/b^2 to clear the fractions
(3/a - 3/b) a^2 b^2
-------------------
(1/a^2 - 1/b^2) a^2b^2
3ab^2 - 3 a^2 b
-------------------
b^2 - a^2
Factor out 3ab on the top
3ab( b-a)
-------------------
b^2 - a^2
The bottom is the difference of squares
3ab( b-a)
-------------------
(b-a) (b+a)
Cancel like terms from the top and bottom
3ab
-------------------
(b+a)
Answer: 140
Step-by-step explanation: It doesn't change because they arethe same proportional angle.
Answer: Choice D 
Reason:
Exponential functions have the variable in the exponent.
Choice A is a polynomial, which means we can rule it out. Choice B is a log function, so we can rule it out also.
Choice C is a rational function because it is a ratio of two polynomials. This rules out choice C.
Choice D is the only function with the variable in the exponent. That is assuming you meant to say
instead of 
X is less than or equal to $30, she can spend $30, she cant spend more, she can spend less.
The answer should look like X<30 with a line under the less than sign, i hope this helps.