Algebra
Calculus
Trigonometry
Matrix
Question
10a2−a−9
Factor the expression
(a−1)(10a+9)
Evaluate
10a2−a−9
Rewrite the expression
10a2+(9−10)a−9
Calculate
10a2+9a−10a−9
Rewrite the expression
a×10a+a×9−10a−9
Factor out a from the expression
a(10a+9)−10a−9
Factor out −1 from the expression
a(10a+9)−(10a+9)
Solution
(a−1)(10a+9)
Show Solution
Find the roots
a1=−109,a2=1
Alternative Form
a1=−0.9,a2=1
Evaluate
10a2−a−9
To find the roots of the expression,set the expression equal to 0
10a2−a−9=0
Factor the expression
More Steps
Evaluate
10a2−a−9
Rewrite the expression
10a2+(9−10)a−9
Calculate
10a2+9a−10a−9
Rewrite the expression
a×10a+a×9−10a−9
Factor out a from the expression
a(10a+9)−10a−9
Factor out −1 from the expression
a(10a+9)−(10a+9)
Factor out 10a+9 from the expression
(a−1)(10a+9)
(a−1)(10a+9)=0
When the product of factors equals 0,at least one factor is 0
a−1=010a+9=0
Solve the equation for a
More Steps
Evaluate
a−1=0
Move the constant to the right-hand side and change its sign
a=0+1
Removing 0 doesn't change the value,so remove it from the expression
a=1
a=110a+9=0
Solve the equation for a
More Steps
Evaluate
10a+9=0
Move the constant to the right-hand side and change its sign
10a=0−9
Removing 0 doesn't change the value,so remove it from the expression
10a=−9
Divide both sides
1010a=10−9
Divide the numbers
a=10−9
Use b−a=−ba=−ba to rewrite the fraction
a=−109
a=1a=−109
Solution
a1=−109,a2=1
Alternative Form
a1=−0.9,a2=1
Show Solution