contestada

y is inversely proportional to V1+x.
When x = 8, y = 2.
Find y when x = 15.

Respuesta :

Answer:

y = 1.5

Step-by-step explanation:

Given x is inversely proportional to [tex]\sqrt{1+x}[/tex] , then the equation relating them is

y = [tex]\frac{k}{\sqrt{1+x} }[/tex] ← k is the constant of proportion

To find k use the condition when x = 8, y = 2

2 = [tex]\frac{k}{\sqrt{1+8} }[/tex] = [tex]\frac{k}{\sqrt{9} }[/tex] = [tex]\frac{k}{3}[/tex] ( multiply both sides by 3 )

6 = k

y = [tex]\frac{6}{\sqrt{1+x} }[/tex] ← equation of proportion

When x = 15 , then

y = [tex]\frac{6}{\sqrt{1+15} }[/tex] = [tex]\frac{6}{\sqrt{16} }[/tex] = [tex]\frac{6}{4}[/tex] = [tex]\frac{3}{2}[/tex] = 1.5