Question
Find the roots
x1=32−22,x2=32+22
Alternative Form
x1≈−0.896805,x2≈2.230139
Evaluate
3x2−4x−6
To find the roots of the expression,set the expression equal to 0
3x2−4x−6=0
Substitute a=3,b=−4 and c=−6 into the quadratic formula x=2a−b±b2−4ac
x=2×34±(−4)2−4×3(−6)
Simplify the expression
x=64±(−4)2−4×3(−6)
Simplify the expression
More Steps

Evaluate
(−4)2−4×3(−6)
Multiply
More Steps

Multiply the terms
4×3(−6)
Rewrite the expression
−4×3×6
Multiply the terms
−72
(−4)2−(−72)
Rewrite the expression
42−(−72)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
42+72
Evaluate the power
16+72
Add the numbers
88
x=64±88
Simplify the radical expression
More Steps

Evaluate
88
Write the expression as a product where the root of one of the factors can be evaluated
4×22
Write the number in exponential form with the base of 2
22×22
The root of a product is equal to the product of the roots of each factor
22×22
Reduce the index of the radical and exponent with 2
222
x=64±222
Separate the equation into 2 possible cases
x=64+222x=64−222
Simplify the expression
More Steps

Evaluate
x=64+222
Divide the terms
More Steps

Evaluate
64+222
Rewrite the expression
62(2+22)
Cancel out the common factor 2
32+22
x=32+22
x=32+22x=64−222
Simplify the expression
More Steps

Evaluate
x=64−222
Divide the terms
More Steps

Evaluate
64−222
Rewrite the expression
62(2−22)
Cancel out the common factor 2
32−22
x=32−22
x=32+22x=32−22
Solution
x1=32−22,x2=32+22
Alternative Form
x1≈−0.896805,x2≈2.230139
Show Solution
