Learn how to solve simplify trigonometric expressions problems step by step online. Solve the quadratic equation 25a^2-40a=-16. Rewrite the equation. To find the roots of a polynomial of the form ax^2+bx+c we use the quadratic formula, where in this case a=25, b=-40 and c=16. Then substitute the values of the coefficients of the equation in the quadratic formula: \displaystyle x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}. Simplifying. To obtain the two solutions, divide the equation in two equations, one when \pm is positive (+), and another when \pm is negative (-).

Solve the quadratic equation 25a^2-40a=-16