If x ∝ √y and y = a², when x = 2a then find x² : y
WBBSE
Class X
Mathematics
Variation
02 Mark
2025
Since x is proportional to √y,
let x = k√y.
Given y = a²,
so √y = a and x = k·a.
We are given x = 2a, which implies k = 2.
Then, x² = (2a)² = 4a²,
so the ratio x² : y = 4a² : a² = 4 : 1.
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