Posted by **latesha** on Saturday, December 17, 2011 at 8:33pm.

Use factoring by grouping to solve the following equation.

4x3 + 8x2 − 9x − 18 = 0

x = 1 (smallest value)

x = 2

x = 3 (largest value)

- math -
**drwls**, Sunday, December 18, 2011 at 8:21am
x = 1 is not a solution. You can easily prove that yourself.

When x = 2,

4x^3 + 8x^2 − 9x − 18 = 28

So that is not a solution, either. Neither is x = 3. How did you come up with your answers?

When x = -2,

-32 +32 +18 -18 = 0

So x+2 is a factor of the polynomial.

The other factor is

(4x^3 + 8x^2 − 9x − 18)/(x+2)

= (4x^2 -9) = (2x +3)(2x-3)

So the other two solutions are

x = 3/2 and x = -3/2

## Answer This Question

## Related Questions

- math - Use factoring by grouping to solve the following equation. 4x^3 + 8x^2 &#...
- probability - Let X be a continuous random variable. We know that it takes ...
- math - Use linear combinations to solve the system 3x − y = −4 &#...
- precalculus - Use the elimination method to find all solutions of the system of ...
- Math - Went ahead and did the HW the teach recommended but she did not post the ...
- biology - Given the part of the molecule shown below, can the underlined atom ...
- math - Find the horizontal and vertical asymptotes of the curve. y = 4+x^4/x^2&#...
- Algebra - Which of the following equations containing grouping symbols is ...
- Math Problem (please help) - Find the zeros of the function algebraically. f(x...
- maths - Find the largest possible value of x^3+y^3+z^3 for realx, y, z, such ...

More Related Questions