When solving these proportions we just remember when moving a number from one side to the other if it started in the numerator it ends up in the denominator and vice versa.
I'll do it in two steps here for teaching purposes; it's not too hard to go directly to the answer.



Answer:
X=9 or x=-9
Step-by-step explanation:
X^2=81
Can be written as
x^2-81=0
Factorize by the property:
a^2-b^2=(a-b)(a+b)
So the expression becomes:
(x-9)(x+9)=0
Therefore, either x-9=0or x+9=0
Then the solutions are x=9 or x=-9
Answer:
Step-by-step explanation:
30*15%=9/2=4.5
so 4.5 would be travelling outside of New York
this gives 30-4.5=25.5 that are not traveling
B.
He has used the highest recommended percentages to calculate the amounts for the three categories.