Solve 15x^2-84x-36=0

To solve 15x^2-84x-36=0 (also written as 15x²-84x-36=0), we notice that it is already in the standard form ax²+bx+c=0.

These are the coefficients, where a=15, b=-84, and c=-36.

We now substitute the coefficients into the quadratic equation formula and simplify. Notice that since coefficient b is a negative number - (-84) becomes +84. Students trip here, so you should sort that part out at the very beginning to avoid making any errors.

This is the first solution.

This is the second solution.