Question
Factor the expression
Factor
−4(4x2+3x+27)
Evaluate
−16x2−12x−108
Solution
−4(4x2+3x+27)
Show Solution
Find the roots
Find the roots of the algebra expression
x1=−83−8347i,x2=−83+8347i
Alternative Form
x1≈−0.375−2.57087i,x2≈−0.375+2.57087i
Evaluate
−16x2−12x−108
To find the roots of the expression,set the expression equal to 0
−16x2−12x−108=0
Multiply both sides
16x2+12x+108=0
Substitute a=16,b=12 and c=108 into the quadratic formula x=2a−b±b2−4ac
x=2×16−12±122−4×16×108
Simplify the expression
x=32−12±122−4×16×108
Simplify the expression
More Steps

Evaluate
122−4×16×108
Multiply the terms
More Steps

Multiply the terms
4×16×108
Multiply the terms
64×108
Multiply the numbers
6912
122−6912
Evaluate the power
144−6912
Subtract the numbers
−6768
x=32−12±−6768
Simplify the radical expression
More Steps

Evaluate
−6768
Evaluate the power
6768×−1
Evaluate the power
6768×i
Evaluate the power
More Steps

Evaluate
6768
Write the expression as a product where the root of one of the factors can be evaluated
144×47
Write the number in exponential form with the base of 12
122×47
The root of a product is equal to the product of the roots of each factor
122×47
Reduce the index of the radical and exponent with 2
1247
1247×i
x=32−12±1247×i
Separate the equation into 2 possible cases
x=32−12+1247×ix=32−12−1247×i
Simplify the expression
More Steps

Evaluate
x=32−12+1247×i
Divide the terms
More Steps

Evaluate
32−12+1247×i
Rewrite the expression
324(−3+347×i)
Cancel out the common factor 4
8−3+347×i
Use b−a=−ba=−ba to rewrite the fraction
−83−347×i
Simplify
−83+8347i
x=−83+8347i
x=−83+8347ix=32−12−1247×i
Simplify the expression
More Steps

Evaluate
x=32−12−1247×i
Divide the terms
More Steps

Evaluate
32−12−1247×i
Rewrite the expression
324(−3−347×i)
Cancel out the common factor 4
8−3−347×i
Use b−a=−ba=−ba to rewrite the fraction
−83+347×i
Simplify
−83−8347i
x=−83−8347i
x=−83+8347ix=−83−8347i
Solution
x1=−83−8347i,x2=−83+8347i
Alternative Form
x1≈−0.375−2.57087i,x2≈−0.375+2.57087i
Show Solution