Algebra
Calculus
Trigonometry
Matrix
Question
Simplify the expression
x2−2x−6
Evaluate
x2−2x−3×2
Solution
x2−2x−6
Show Solution
Find the roots
x1=1−7,x2=1+7
Alternative Form
x1≈−1.645751,x2≈3.645751
Evaluate
x2−2x−3×2
To find the roots of the expression,set the expression equal to 0
x2−2x−3×2=0
Multiply the numbers
x2−2x−6=0
Substitute a=1,b=−2 and c=−6 into the quadratic formula x=2a−b±b2−4ac
x=22±(−2)2−4(−6)
Simplify the expression
More Steps
Evaluate
(−2)2−4(−6)
Multiply the numbers
More Steps
Evaluate
4(−6)
Multiplying or dividing an odd number of negative terms equals a negative
−4×6
Multiply the numbers
−24
(−2)2−(−24)
Rewrite the expression
22−(−24)
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+24
Evaluate the power
4+24
Add the numbers
28
x=22±28
Simplify the radical expression
More Steps
Evaluate
28
Write the expression as a product where the root of one of the factors can be evaluated
4×7
Write the number in exponential form with the base of 2
22×7
The root of a product is equal to the product of the roots of each factor
22×7
Reduce the index of the radical and exponent with 2
27
x=22±27
Separate the equation into 2 possible cases
x=22+27x=22−27
Simplify the expression
More Steps
Evaluate
x=22+27
Divide the terms
More Steps
Evaluate
22+27
Rewrite the expression
22(1+7)
Reduce the fraction
1+7
x=1+7
x=1+7x=22−27
Simplify the expression
More Steps
Evaluate
x=22−27
Divide the terms
More Steps
Evaluate
22−27
Rewrite the expression
22(1−7)
Reduce the fraction
1−7
x=1−7
x=1+7x=1−7
Solution
x1=1−7,x2=1+7
Alternative Form
x1≈−1.645751,x2≈3.645751
Show Solution