Algebra 2

posted by .

Solve: 0 = x3 + 5x2 + 2x – 8

Solve: 0 = x3 – x2 – 11x – 10

  • Algebra 2 -

    use your graphing calculator or plot it on a graph

  • Algebra 2 -

    Use the Rational Roots Theorem.

    Suppose

    a x^n + b x^(n-1) + .... e = 0

    If x is a rational number of the form p/q with p and q integers that don't have factors in common (i.e. the fraction p/q is simplified as much as possible), then p must divide e and q must divide a.

    In case of the equation:

    x^3 + 5x^2 + 2x – 8 = 0

    this means that x = integer that divides 8. x = 1, x= -2 and x = -4 are solutions.

  • Algebra 2 -

    x^3 – x^2 – 11x – 10 = 0

    Assuming again that the roots are rational numbers, it follows from the Rational Roots Theorem that the roots are integers that divide the number 10.

    So, the only possible rational roots are:

    x = -10, x = -5, x = -2, x = -1, x = 1, x = 2, x = 5, x = 10

    Only x = -2 satisfies the equation.

    Factoring the polynomial gives:

    x^3 – x^2 – 11x – 10 =

    (x+2)(x^2 -3x - 5)

    The zeroes of the quadratic factor are the other zeroes (you already know that they cannot be rational).

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. algebra PLZ HELP!!!

    y= 9/11x-17 9x-10y=179 You need to use parentheses to tell us what the problem is. Is equation 1, y = 9/(11x-17) or is it y = (9/11)x - 17?
  2. Intermediate Algebra

    Combine like terms: -3x^2+2x-4x^2-9+6x-2x^2+8 Solve for x: 8x-11= -11x+18 Solve for x: -2(x-5)+7=z-8-5x Solve for x: (x-2)/5 - 3/2= (x+1)/10 Translate to an algebra statement; do not solve: Seven times the difference of six and a twice …
  3. algebra

    solve for x 8x - 11 = -11x + 18
  4. Algebra......Help Quick!!

    12a^3bc-18a^2bc^2+6a^2c, x^2+20x+36, 12x^4-8x^3-4x^2, x^2+36x, 9x^2+6x+1, 6x^3+11x-10, x^2+3x-6..............can someone please help me solve some of these problems if not all. I have forgotten how to solve them can someone please …
  5. algebra

    -6-11x=-136 solve
  6. 9th Grade Algebra

    4x^2-11x+3=5x+4 How do I solve this?
  7. algebra

    Solve with fractions. 6x^(2/3)-11x^(1/3)+4=0 How do I solve?
  8. Algebra 2 Help!

    1.) Simplify the expression. [sqrt3 + 2i][sqrt3 - 2i] 2.) Solve using the square root property. (y - 4)2 = -18 3.) Rewrite the the function in vertex form. You may use completing the square or an alternate method. f(x) = 5x2 - 10x …
  9. Calculus

    I've done everything I can think of to solve this, but I have no idea. Find the derivative: y = sq rt{11x + sqrt[11x + sqrt(11x)]}
  10. math

    solve the system of equations for x and y { x^2 - 11x -y =-24 x^2 - 11x + y = -24

More Similar Questions