Algebra
Calculus
Trigonometry
Matrix
Question
Factor the expression
(b−9)(b+1)
Evaluate
b2−8b−9
Rewrite the expression
b2+(1−9)b−9
Calculate
b2+b−9b−9
Rewrite the expression
b×b+b−9b−9
Factor out b from the expression
b(b+1)−9b−9
Factor out −9 from the expression
b(b+1)−9(b+1)
Solution
(b−9)(b+1)
Show Solution
Find the roots
b1=−1,b2=9
Evaluate
b2−8b−9
To find the roots of the expression,set the expression equal to 0
b2−8b−9=0
Factor the expression
More Steps
Evaluate
b2−8b−9
Rewrite the expression
b2+(1−9)b−9
Calculate
b2+b−9b−9
Rewrite the expression
b×b+b−9b−9
Factor out b from the expression
b(b+1)−9b−9
Factor out −9 from the expression
b(b+1)−9(b+1)
Factor out b+1 from the expression
(b−9)(b+1)
(b−9)(b+1)=0
When the product of factors equals 0,at least one factor is 0
b−9=0b+1=0
Solve the equation for b
More Steps
Evaluate
b−9=0
Move the constant to the right-hand side and change its sign
b=0+9
Removing 0 doesn't change the value,so remove it from the expression
b=9
b=9b+1=0
Solve the equation for b
More Steps
Evaluate
b+1=0
Move the constant to the right-hand side and change its sign
b=0−1
Removing 0 doesn't change the value,so remove it from the expression
b=−1
b=9b=−1
Solution
b1=−1,b2=9
Show Solution