Solve 10k^3-15k^26k-9

Question

Simplify the expression

- 80 k^{3} - 9

Show Solution

k = - \frac{3 900}{20}

Alternative Form

k \approx - 0.482745

Evaluate

10 k^{3} - 15 k^{2} \times 6 k - 9

To find the roots of the expression,set the expression equal to 0

10 k^{3} - 15 k^{2} \times 6 k - 9 = 0

Multiply

More Steps

10 k^{3} - 90 k^{3} - 9 = 0

Subtract the terms

More Steps

- 80 k^{3} - 9 = 0

Move the constant to the right-hand side and change its sign

- 80 k^{3} = 0 + 9

Removing 0 doesn't change the value,so remove it from the expression

- 80 k^{3} = 9

Change the signs on both sides of the equation

80 k^{3} = - 9

Divide both sides

\frac{80 k ^{3}}{80} = \frac{- 9}{80}

Divide the numbers

k^{3} = \frac{- 9}{80}

Use \frac{- a}{b} = \frac{a}{- b} = - \frac{a}{b} to rewrite the fraction

k^{3} = - \frac{9}{80}

Take the 3 -th root on both sides of the equation

3 k^{3} = 3 - \frac{9}{80}

Calculate

k = 3 - \frac{9}{80}

Solution

More Steps

k = - \frac{3 900}{20}

Alternative Form

k \approx - 0.482745

Show Solution