algebra

Please solve the following problem by using factoring and the zero-product property.

9r^2-30r+21=-4

Thanks

  1. 👍 0
  2. 👎 0
  3. 👁 175
  1. 9r^2-30r+21 = -4
    9r^2-30r+25 = 0

    Note that 9 and 25 are perfect squares, so a good thing to try is

    (3r-5)^2 = 0

    Yep, that's it.

    So, there is a double root of x = 5/3

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. geometry

    Name the property of equality or congruence that justifies going from the first statement to the second statement. StartFraction x Over 2 EndFraction equals 3x2=3 x equals 6x=6 symmetric property of congruencesymmetric property of

  2. Algebra

    Which property is illustrated by the following statement? (7p)mn = 7p(mn) a. Commutative Property of Multiplication b. Associative Property of Multiplication(?) c. Inverse Property of Multiplication d. Commutative Property of

  3. Geometry

    How do I solve this? Complete the two-column proof. Given : 11x – 6y = –1; x = 8 Prove: 89/6= y 11x – 6y = –1; x = 8 88 – 6y = –1 –6y = –89 y = 89/6 89/6= y • a. Given; b. Symmetric Property of Equality; c.

  4. MTH HELP

    5)Which property is illustrated by the following statement ? 3z+4=4+3z A)Associative property of addition B)Commutative property of multiplication C)Inverse property of multiplication D)commutative property of addition 12) What is

  1. Algebra A

    write a short story problem that can be solved in one step. Write an equation that represents the problem. Name the property used to solve the problem, and then solve the problem. PLEASE HELP WITH THIS ASAP!!!

  2. maths

    the sum of N positive integers is 19. what is the maximum possible product of these N numbers? thx. Nice problem. Let's look at some cases 1. N=2 clearly our only logical choices are 9,10 for a product of 90 It should be obvious

  3. Algebra A

    write a short story problem that can be solved in one step. Write an equation that represents the problem. Name the property used to solve the problem, and then solve the problem. can anyone give me the problem and the name of the

  4. math

    Which property would allow you to use mental computation to simplify the problem 27 + 15 + 3 + 5? 1) commutative property of addition 2) distributive property 3) additive identity 4) additive inverse

  1. GENERAL CHEMISTRY

    CALCULATE THE pH AND HYDROLYSIS IN 0.10 M AlCl3 SOLUTION.Ka = 1.2 X 10-5 FOR [Al(OH2)6]+3,OFTEN ABBREVIATED Al+3.TELL WHETHER pH IS ACID OR BASE.GIVE IONIC EQUATION. Help us a little by telling us how much you know to do and

  2. Math

    Solve by factoring. x² - 121 = 0 0 -11 11 11, -11 Solve by factoring. m² + 8m + 7 = 0 8,7 -7, 1 -7, -1 7, 1

  3. Algebra Zero Product Rule

    I'm working with the zero product rule and I've somehow lost my way on a certain problem pattern. (x+8)(x-3)= -30 Is the pattern and the answer in the book says -2 or -3, but when I do the problem... x²+5x-24= -30 x²+5x+6= 0

  4. algebra

    Solve the equation using the zero-product property. -9n(5n-5) a. -1/9, 1 b. 0,1***** c. -1/9,-1 d. 0,-1 Use the quadratic formula to solve the equation. if necessary, round to the nearest hundredth. x^2-6=x a. x=2,3 b. x=-2,3

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