math

Y is directly proportional to the square of x.
Find the percentage increase in value of y when x is doubled

  1. 👍
  2. 👎
  3. 👁
  1. Y=kx^2
    When x is doubled
    Y=(2x)^2
    Therefore Y=4x^2

    Percentage increase=(3kx^2)/kx^2 ×100%
    =300%
    Is it good?

    1. 👍
    2. 👎
  2. correct, except I would keep the k in the calculation

    old y = k x^2
    new y = k (4x^2)
    change in y = 3k x^2
    percentage change = 3k x^2/(k x^2) = 3
    or 300%

    e.g. enter 1 and 4 for the following applet,
    http://www.marshu.com/articles/calculate-percentage-increase-decrease-percent-calculator.php

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. math

    it is given that y is directly proportional to xn. write down the value of n when (i) y m square is the area of a square length x m . (ii) y cm cube is the volume of a cube of length x cm.

  2. physics-speed

    i need help with this one thanks A particle starts from rest and is acted on by a net force that does work at a rate that is proportional to the time t. The speed of the particle is proportional to: a. sq. root t b. t c. t^2

  3. maths

    Y is directly proportional to the square of x. Find percentage increase in value of y when value of x is doubled

  4. chemistry - exam practice help!!

    For the cell shown below, which will increase the cell voltage the most? Fe2+ | Fe3+ || Cu2+ | Cu A) Halve[Cu2+] B) Double[Cu2+] C) Double[Fe2+] D) Halve[Fe2+] E) Cut Cu electrode in half ... Ecell = E0 cell + 0.059/n *

  1. Maths

    The braking distance of a car is directly proportional to te square of it's speed. When the speed is p metres per second, the braking distance is 6m. When the speed is increased by 300%, find (a) an expression for speed of the car

  2. math

    When a stone is thrown upwards with an initial velocity of v metres per second, it reaches a maximum height of h metres. h is directly proportional to the square of v. Calculate the value of v when h = 50 Please help

  3. mathematics

    it is given that y is directly proportional to x^n write down the value of n when y m square is the area of a square of length x m

  4. Math

    Suppose A is directly proportional to the square of B,and A=45 when B=3. a)Find the constant of proportionality b)Write the formula for A in terms of B c)Use your formula to find A when B=6

  1. Chemistry

    I might be overthinking this but my reference books, note and the internet don't have much on this topic. What is the relationship between the solubility product constant Ksp and temperature? A. They are directly proportional B.

  2. mathematics

    If p is directly proportional q and p=4.5 when q = 12 ,find the relationship between p and q,p when q= 16,q when p= 2.4

  3. Physics answer check pls

    1. The electrostatic force between two charges is originally F. Which expression represents the new electrostatic force between the two charges if one charge doubles and the other one is divided by three? A. 3/2 F B. 2/3 F C. 1/6

  4. math

    In physics, Ohm's law says that current through a wire, I, is directly proportional to voltage, V, and inversely proportional to resistance, R: I=V/R. It's also true that resistance is directly proportional to the length of the

You can view more similar questions or ask a new question.