Solve Using the Quadratic Formula x^2+2x-8=0

Problem

x2+2*x−8=0

Solution

1. Identify the coefficients a b and c from the quadratic equation in the form a*x2+b*x+c=0

a=1

b=2

c=−8

2. State the quadratic formula used to find the roots of the equation.

x=(−b±√(,b2−4*a*c))/(2*a)

3. Substitute the identified values of a b and c into the formula.

x=(−(2)±√(,(2)2−4*(1)*(−8)))/(2*(1))

4. Simplify the expression inside the square root (the discriminant).

x=(−2±√(,4+32))/2

x=(−2±√(,36))/2

5. Evaluate the square root and simplify the fraction.

x=(−2±6)/2

6. Solve for the two possible values of x by calculating both the plus and minus cases.

x=(−2+6)/2=4/2=2

x=(−2−6)/2=(−8)/2=−4

Final Answer

x=2,−4

Want more problems? Check here!