Algebra
Calculus
Trigonometry
Matrix
Question
Factor the expression
(v−5)(v+4)
Evaluate
v2−v−20
Rewrite the expression
v2+(4−5)v−20
Calculate
v2+4v−5v−20
Rewrite the expression
v×v+v×4−5v−5×4
Factor out v from the expression
v(v+4)−5v−5×4
Factor out −5 from the expression
v(v+4)−5(v+4)
Solution
(v−5)(v+4)
Show Solution
Find the roots
v1=−4,v2=5
Evaluate
v2−v−20
To find the roots of the expression,set the expression equal to 0
v2−v−20=0
Factor the expression
More Steps
Evaluate
v2−v−20
Rewrite the expression
v2+(4−5)v−20
Calculate
v2+4v−5v−20
Rewrite the expression
v×v+v×4−5v−5×4
Factor out v from the expression
v(v+4)−5v−5×4
Factor out −5 from the expression
v(v+4)−5(v+4)
Factor out v+4 from the expression
(v−5)(v+4)
(v−5)(v+4)=0
When the product of factors equals 0,at least one factor is 0
v−5=0v+4=0
Solve the equation for v
More Steps
Evaluate
v−5=0
Move the constant to the right-hand side and change its sign
v=0+5
Removing 0 doesn't change the value,so remove it from the expression
v=5
v=5v+4=0
Solve the equation for v
More Steps
Evaluate
v+4=0
Move the constant to the right-hand side and change its sign
v=0−4
Removing 0 doesn't change the value,so remove it from the expression
v=−4
v=5v=−4
Solution
v1=−4,v2=5
Show Solution