Question
Solve the quadratic equation
Solve using the quadratic formula
Solve by completing the square
Solve using the PQ formula
x1=1−11,x2=1+11
Alternative Form
x1≈−2.316625,x2≈4.316625
Evaluate
x2−2x−10=0
Substitute a=1,b=−2 and c=−10 into the quadratic formula x=2a−b±b2−4ac
x=22±(−2)2−4(−10)
Simplify the expression
More Steps

Evaluate
(−2)2−4(−10)
Multiply the numbers
More Steps

Evaluate
4(−10)
Multiplying or dividing an odd number of negative terms equals a negative
−4×10
Multiply the numbers
−40
(−2)2−(−40)
Rewrite the expression
22−(−40)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
22+40
Evaluate the power
4+40
Add the numbers
44
x=22±44
Simplify the radical expression
More Steps

Evaluate
44
Write the expression as a product where the root of one of the factors can be evaluated
4×11
Write the number in exponential form with the base of 2
22×11
The root of a product is equal to the product of the roots of each factor
22×11
Reduce the index of the radical and exponent with 2
211
x=22±211
Separate the equation into 2 possible cases
x=22+211x=22−211
Simplify the expression
More Steps

Evaluate
x=22+211
Divide the terms
More Steps

Evaluate
22+211
Rewrite the expression
22(1+11)
Reduce the fraction
1+11
x=1+11
x=1+11x=22−211
Simplify the expression
More Steps

Evaluate
x=22−211
Divide the terms
More Steps

Evaluate
22−211
Rewrite the expression
22(1−11)
Reduce the fraction
1−11
x=1−11
x=1+11x=1−11
Solution
x1=1−11,x2=1+11
Alternative Form
x1≈−2.316625,x2≈4.316625
Show Solution
