Algebra
Calculus
Trigonometry
Matrix
Question
Find the roots
x1=2−25,x2=2+25
Alternative Form
x1≈−2.472136,x2≈6.472136
Evaluate
x2−4x−16
To find the roots of the expression,set the expression equal to 0
x2−4x−16=0
Substitute a=1,b=−4 and c=−16 into the quadratic formula x=2a−b±b2−4ac
x=24±(−4)2−4(−16)
Simplify the expression
More Steps
Evaluate
(−4)2−4(−16)
Multiply the numbers
More Steps
Evaluate
4(−16)
Multiplying or dividing an odd number of negative terms equals a negative
−4×16
Multiply the numbers
−64
(−4)2−(−64)
Rewrite the expression
42−(−64)
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+64
Evaluate the power
16+64
Add the numbers
80
x=24±80
Simplify the radical expression
More Steps
Evaluate
80
Write the expression as a product where the root of one of the factors can be evaluated
16×5
Write the number in exponential form with the base of 4
42×5
The root of a product is equal to the product of the roots of each factor
42×5
Reduce the index of the radical and exponent with 2
45
x=24±45
Separate the equation into 2 possible cases
x=24+45x=24−45
Simplify the expression
More Steps
Evaluate
x=24+45
Divide the terms
More Steps
Evaluate
24+45
Rewrite the expression
22(2+25)
Reduce the fraction
2+25
x=2+25
x=2+25x=24−45
Simplify the expression
More Steps
Evaluate
x=24−45
Divide the terms
More Steps
Evaluate
24−45
Rewrite the expression
22(2−25)
Reduce the fraction
2−25
x=2−25
x=2+25x=2−25
Solution
x1=2−25,x2=2+25
Alternative Form
x1≈−2.472136,x2≈6.472136
Show Solution
