Question
Find the roots
x1=21−13,x2=21+13
Alternative Form
x1≈−1.302776,x2≈2.302776
Evaluate
x2−x−3
To find the roots of the expression,set the expression equal to 0
x2−x−3=0
Substitute a=1,b=−1 and c=−3 into the quadratic formula x=2a−b±b2−4ac
x=21±(−1)2−4(−3)
Simplify the expression
More Steps

Evaluate
(−1)2−4(−3)
Evaluate the power
1−4(−3)
Multiply the numbers
More Steps

Evaluate
4(−3)
Multiplying or dividing an odd number of negative terms equals a negative
−4×3
Multiply the numbers
−12
1−(−12)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
1+12
Add the numbers
13
x=21±13
Separate the equation into 2 possible cases
x=21+13x=21−13
Solution
x1=21−13,x2=21+13
Alternative Form
x1≈−1.302776,x2≈2.302776
Show Solution
