Verified Answer :

carlosego

Since the variation is direct, then we have an equation of the form:
 \(y = kx ^ 2\)
 From here, we must find the value of k.
 For this, we use the following data:
 y = 245 when x = 7
 Substituting values we have:
 \(245 = k7 ^ 2\)
 Rewriting we have:
 \(245 = 49k\)
 Clearing k we have:
 \(k = \frac{245}{49}\)
 \(k = 5\)
 Therefore, the equation is given by:
 \(y = 5x ^ 2\)
 Evaluating the equation for x = 9 we have:
 \(y = 5 (9) ^ 2 y = 5 (81) y = 405\)
 Answer
 The value of y when x = 9 is:
 \(y = 405\)

Related Questions