Respuesta :

Answer:

see explanation

Step-by-step explanation:

(a)

Given y is inversely proportional to x² then the equation relating them is

y = [tex]\frac{k\\}{x^2}[/tex] ← k is the constant of variation

To find k use any ordered pair from the table.

Using (1, 4 ) , then

4 = [tex]\frac{k}{1^2}[/tex] = [tex]\frac{k}{1}[/tex] ( multiply both sides by 1

4 = k

y = [tex]\frac{4}{x^2}[/tex] ← equation of variation

(b)

When y = 25 , then

25 = [tex]\frac{4}{x^2}[/tex] ( multiply both sides by x² )

25x² = 4 ( divide both sides by 25 )

x² = [tex]\frac{4}{25}[/tex] ( take the square root of both sides )

x = ± [tex]\sqrt{\frac{4}{25} }[/tex] = ± [tex]\frac{2}{5}[/tex]

Since x > 0 then x = [tex]\frac{2}{5}[/tex]