Algebra
Calculus
Trigonometry
Matrix
Question
Factor the expression
(x−9)(x+1)
Evaluate
x2−8x−9
Rewrite the expression
x2+(1−9)x−9
Calculate
x2+x−9x−9
Rewrite the expression
x×x+x−9x−9
Factor out x from the expression
x(x+1)−9x−9
Factor out −9 from the expression
x(x+1)−9(x+1)
Solution
(x−9)(x+1)
Show Solution
Find the roots
x1=−1,x2=9
Evaluate
x2−8x−9
To find the roots of the expression,set the expression equal to 0
x2−8x−9=0
Factor the expression
More Steps
Evaluate
x2−8x−9
Rewrite the expression
x2+(1−9)x−9
Calculate
x2+x−9x−9
Rewrite the expression
x×x+x−9x−9
Factor out x from the expression
x(x+1)−9x−9
Factor out −9 from the expression
x(x+1)−9(x+1)
Factor out x+1 from the expression
(x−9)(x+1)
(x−9)(x+1)=0
When the product of factors equals 0,at least one factor is 0
x−9=0x+1=0
Solve the equation for x
More Steps
Evaluate
x−9=0
Move the constant to the right-hand side and change its sign
x=0+9
Removing 0 doesn't change the value,so remove it from the expression
x=9
x=9x+1=0
Solve the equation for x
More Steps
Evaluate
x+1=0
Move the constant to the right-hand side and change its sign
x=0−1
Removing 0 doesn't change the value,so remove it from the expression
x=−1
x=9x=−1
Solution
x1=−1,x2=9
Show Solution