Answer:
Problem 7) C
Problem 8) B
Step-by-step explanation:
Recall that inverse variation has the form:
[tex]\displaystyle y=\frac{k}{x}[/tex]
Where k is the constant of variation.
Problem 7)
We are given that y = 39 when x = 1/3. Thus:
[tex]\displaystyle 39=\frac{k}{{}^{1}\!/ \!{}_{3}}[/tex]
Solve for k:
[tex]\displaystyle k=\frac{1}{3}(39)=13[/tex]
Hence, our equation is:
[tex]\displaystyle y=\frac{13}{x}[/tex]
Then when x = 26, y equals:
[tex]\displaystyle y=\frac{13}{(26)}=\frac{1}{2}[/tex]
Problem 8)
We are given that y = 25 when x = -1/5. Thus:
[tex]\displaystyle 25=\frac{k}{-{}^{1}\!/ \!{}_{5}}[/tex]
Solve for k:
[tex]\displaystyle k=-\frac{1}{5}(25)=-5[/tex]
Hence, our equation is:
[tex]\displaystyle y=-\frac{5}{x}[/tex]
