Find the

Find the number x, which if it increases by 2, then its square increases by 21 percent.

Correct result:

x =  20
y =  -0.9524


q=21%=1+21100=1.21  (x+2)2=x2q  (x+2)2=x2 1.21 0.21x2+4x+4=0 0.21x24x4=0  a=0.21;b=4;c=4 D=b24ac=4240.21(4)=19.36 D>0  x1,2=b±D2a=4±19.360.42 x1,2=9.52380952±10.4761904762 x1=20 x2=0.952380952381   Factored form of the equation:  0.21(x20)(x+0.952380952381)=0  x=x1=20

Our quadratic equation calculator calculates it.


We would be pleased if you find an error in the word problem, spelling mistakes, or inaccuracies and send it to us. Thank you!

Showing 0 comments:

Tips to related online calculators
Looking for help with calculating roots of a quadratic equation?
Our percentage calculator will help you quickly calculate various typical tasks with percentages.
Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?

Related math problems and questions:

  • Square
    percent Suppose the square's sides' length decreases by a 25% decrease in the content area of 28 cm2. Determine the side length of the original square.
  • Square sides
    square_7 If the square side increases by 28%, the square circumference increases by 11.2 meters. Find the length of the original square side.
  • Unknown number 7
    graph-parabola Calculate unknown number whose 12th power when divided by the 9th power get a number 27 times greater than the unknown number. Determine the unknown number.
  • Square side
    squares If we enlarge the square side a = 5m, its area will increase by 10,25%. How many percent will the side of the square increase? How many percent will it increase the circumference of the square?
  • The ball
    sphere4 The ball has a radius of 2m. What percentage of the surface and volume is another sphere whose radius is 20% larger?
  • Cuboid enlargement
    cubes_12 By how many percent increases the volume of cuboid if its every dimension increases by 30%?
  • Unknown number 4
    ninth I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking?
  • Completing square
    eq2_5 Solve the quadratic equation: m2=4m+20 using completing the square method
  • Find the 2
    square_4 Find the term independent of x in the expansion of (4x3+1/2x)8
  • Two pipes
    roura_1 How long will the pool be filled with a double supply pipe if it takes the pool to fill the first pipe by 4 hours longer and the second pipe 9 hours longer than both pipes open at the same time?
  • Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  • Two-digit number
    numbers_1 Digit sum of thinking two-digit natural number is 11. When it exchanging a sequence of digits, given a number which is 27 less than the thinking number. Find out which number I think.
  • The sum
    eq222_1 The sum of the squares of two immediately following natural numbers is 1201. Find these numbers.
  • The number 72
    percent_2 The number 72 increase by 25%. By how much % will you have to reduce the number you created to get the number 72 again?
  • Combinations
    kvadrat_3 If the number of elements increase by 3, it increases the number of combinations of the second class of these elements 5 times. How many are the elements?
  • Trapezoid 15
    trapezoid3 Area of trapezoid is 266. What value is x if bases b1 is 2x-3, b2 is 2x+1 and height h is x+4
  • Substitution method
    500px-Sine_cosine_plot.svg Solve goniometric equation: sin4 θ - 1/cos2 θ=cos2 θ - 2