Solve the equation 3x² - 4x - 4 = 0 by using formula giving answer correct to three decimal places.

The following table shows the marks obtained (out of 100) by different students of class X.

Taking suitable scales on both the axes, draw a histogram and use it to estimate mode.

The radii of two concentric circles are 6 cm and 10 cm respectively. Find the length of the chord of the bigger circle which is tangent to smaller circle.

If x² - 3x + 2 is a factor of x³ - ax² + b, find the values of a and b.