Algebra
Calculus
Trigonometry
Matrix
Question
Simplify the expression
x2+7x−18
Evaluate
(x+9)(x−2)
Apply the distributive property
x×x−x×2+9x−9×2
Multiply the terms
x2−x×2+9x−9×2
Use the commutative property to reorder the terms
x2−2x+9x−9×2
Multiply the numbers
x2−2x+9x−18
Solution
More Steps
Evaluate
−2x+9x
Collect like terms by calculating the sum or difference of their coefficients
(−2+9)x
Add the numbers
7x
x2+7x−18
Show Solution
Find the roots
x1=−9,x2=2
Evaluate
(x+9)(x−2)
To find the roots of the expression,set the expression equal to 0
(x+9)(x−2)=0
Separate the equation into 2 possible cases
x+9=0x−2=0
Solve the equation
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−2=0
Solve the equation
More Steps
Evaluate
x−2=0
Move the constant to the right-hand side and change its sign
x=0+2
Removing 0 doesn't change the value,so remove it from the expression
x=2
x=−9x=2
Solution
x1=−9,x2=2
Show Solution