Question

How to solve quadratics using r² - 10r =39?

Answer 1

To solve the quadratic equation r² - 10r = 39, rearrange it to the standard form, r² - 10r - 39 = 0, and then apply the quadratic formula with a=1, b=-10, and c=-39 to find the solutions.

Step-by-step explanation:

To solve the quadratic equation r² - 10r = 39, we must first rearrange the equation to bring it to the standard form of a quadratic equation, which is ax² + bx + c = 0. For this particular equation, we follow the given steps:

1. Add 39 to both sides of the equation to gather all terms on one side, resulting in r² - 10r - 39 = 0.
2. Once in standard form, we can apply the quadratic formula, which is x = (-b ± √(b² - 4ac))/(2a). In this equation, a = 1, b = -10, and c = -39.
3. Substitute the values of a, b, and c into the quadratic formula and solve for r.

Using these steps, you should be able to find the two values of r that satisfy the original equation.