Solve Using the Quadratic Formula x^2+7x-8=0

Problem

x2+7*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=7

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 into the quadratic formula.

x=(−7±√(,7−4*(1)*(−8)))/(2*(1))

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

x=(−7±√(,49+32))/2

x=(−7±√(,81))/2

5. Evaluate the square root and solve for the two possible values of x

x=(−7±9)/2

6. Calculate the first solution using the plus sign.

x=(−7+9)/2=2/2=1

7. Calculate the second solution using the minus sign.

x=(−7−9)/2=(−16)/2=−8

Final Answer

x=1,−8

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