Answer :
Answer:
y = 125
Step-by-step explanation:
Given that,
y is directly proportional to x² i.e.
[tex]y=kx^2[/tex]
k is a constant of proportionality
Put y = 20 and x = 2 in the given equation to find k.
[tex]k=\dfrac{y}{x^2}\\\\k=\dfrac{20}{(2)^2}\\\\k=5[/tex]
Now put k = 5 and x = 5 in the given equation to find y.
[tex]y=5\times (5)^2\\\\y=125[/tex]
So, the value of y is equal to 125.