Answer:The quadratic formula helps us solve any quadratic equation. First, we bring the equation to the form ax²+bx+c=0, where a, b, and c are coefficients. Then, we plug these coefficients in the formula: (-b±√(b²-4ac))/(2a) .The four methods of solving a quadratic equation are factoring, using the square roots, completing the square and the quadratic formula.
Step-by-step explanation: 6x² + 11x - 35 = 0.
2x² - 4x - 2 = 0.
-4x² - 7x +12 = 0.
20x² -15x - 10 = 0.
x² -x - 3 = 0.
5x² - 2x - 9 = 0.
3x² + 4x + 2 = 0.
-x² +6x + 18 = 0.