Answer:
(-2,-1)
Step-by-step explanation:
 
        
             
        
        
        
2/3 n = -12 Write equation
(3/2) 2/3n = -12/1 (3/2) Isolate n 
n = -36/2 Simplify
n = -18 Answer
        
                    
             
        
        
        
Answer:
Ivy is 6 years old and Rose is 12 years old.
Step-by-step explanation:
To solve this problem, two variables are necessary since we have two unknown variables: Ivy's age and Rose's age.
Ivy's age will be 
and Rose's age will be 
"Ivy is half as old as her sister":

this will be our <u>fist equation.</u>
"In six years, Ivy will be two-thirds as old as Rose"
in six years Ivy will have  years, and Rose will have
 years, and Rose will have  years, so for this sentence we have the equation:
 years, so for this sentence we have the equation:

this will be our <u>second equation.</u>
Substituting the value of x from the first equation into the second, and solving for y(Rose):

Rose is 12 years old.
and Ivy (using the fist equation):

Ivy is 6 years old.
 
        
             
        
        
        
Answer:
19 (using "3.14" as pi)
18.99036781...(using pi button)
Step-by-step explanation:
Formula: C=dπ
so, (59.66)=dπ 
you would divide circumference (C) by pi which will get you the answers above :) 
hope this helped