Question
Simplify the expression
28z2−2z+6
Evaluate
(7z2×4)−(2z−6)
Multiply the terms
28z2−(2z−6)
Solution
28z2−2z+6
Show Solution

Factor the expression
2(14z2−z+3)
Evaluate
(7z2×4)−(2z−6)
Multiply the terms
28z2−(2z−6)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
28z2−2z+6
Solution
2(14z2−z+3)
Show Solution

Find the roots
z1=281−28167i,z2=281+28167i
Alternative Form
z1≈0.035˙71428˙−0.46153i,z2≈0.035˙71428˙+0.46153i
Evaluate
(7z2×4)−(2z−6)
To find the roots of the expression,set the expression equal to 0
(7z2×4)−(2z−6)=0
Multiply the terms
28z2−(2z−6)=0
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
28z2−2z+6=0
Substitute a=28,b=−2 and c=6 into the quadratic formula z=2a−b±b2−4ac
z=2×282±(−2)2−4×28×6
Simplify the expression
z=562±(−2)2−4×28×6
Simplify the expression
More Steps

Evaluate
(−2)2−4×28×6
Multiply the terms
More Steps

Multiply the terms
4×28×6
Multiply the terms
112×6
Multiply the numbers
672
(−2)2−672
Rewrite the expression
22−672
Evaluate the power
4−672
Subtract the numbers
−668
z=562±−668
Simplify the radical expression
More Steps

Evaluate
−668
Evaluate the power
668×−1
Evaluate the power
668×i
Evaluate the power
More Steps

Evaluate
668
Write the expression as a product where the root of one of the factors can be evaluated
4×167
Write the number in exponential form with the base of 2
22×167
The root of a product is equal to the product of the roots of each factor
22×167
Reduce the index of the radical and exponent with 2
2167
2167×i
z=562±2167×i
Separate the equation into 2 possible cases
z=562+2167×iz=562−2167×i
Simplify the expression
More Steps

Evaluate
z=562+2167×i
Divide the terms
More Steps

Evaluate
562+2167×i
Rewrite the expression
562(1+167×i)
Cancel out the common factor 2
281+167×i
Simplify
281+28167i
z=281+28167i
z=281+28167iz=562−2167×i
Simplify the expression
More Steps

Evaluate
z=562−2167×i
Divide the terms
More Steps

Evaluate
562−2167×i
Rewrite the expression
562(1−167×i)
Cancel out the common factor 2
281−167×i
Simplify
281−28167i
z=281−28167i
z=281+28167iz=281−28167i
Solution
z1=281−28167i,z2=281+28167i
Alternative Form
z1≈0.035˙71428˙−0.46153i,z2≈0.035˙71428˙+0.46153i
Show Solution
