Solve each equation using the Quadratic Formula 1. $4 x^{2}+11 x-20=0$

Step 1 ：The quadratic formula is given by \(x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\), where \(a\), \(b\), and \(c\) are the coefficients of the quadratic equation \(ax^2 + bx + c = 0\). In this case, \(a = 4\), \(b = 11\), and \(c = -20\). We will substitute these values into the quadratic formula to find the solutions for \(x\).

Step 2 ：Substituting \(a = 4\), \(b = 11\), and \(c = -20\) into the quadratic formula, we get \(x = \frac{-11 \pm \sqrt{11^2 - 4*4*(-20)}}{2*4}\).

Step 3 ：Solving the above equation, we get two solutions for \(x\), which are \(x = -4.0\) and \(x = 1.25\).

Step 4 ：Final Answer: The solutions to the equation \(4 x^{2}+11 x-20=0\) are \(x = -4.0\) and \(x = 1.25\). Therefore, the solutions are \(\boxed{-4.0}\) and \(\boxed{1.25}\).