Question
Simplify the expression
8z4−28z2
Evaluate
z2×8z2−6z2−10z2−7z2−5z2
Multiply
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Multiply the terms
z2×8z2
Multiply the terms with the same base by adding their exponents
z2+2×8
Add the numbers
z4×8
Use the commutative property to reorder the terms
8z4
8z4−6z2−10z2−7z2−5z2
Solution
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Evaluate
−6z2−10z2−7z2−5z2
Collect like terms by calculating the sum or difference of their coefficients
(−6−10−7−5)z2
Subtract the numbers
−28z2
8z4−28z2
Show Solution

Factor the expression
4z2(2z2−7)
Evaluate
z2×8z2−6z2−10z2−7z2−5z2
Multiply
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Multiply the terms
z2×8z2
Multiply the terms with the same base by adding their exponents
z2+2×8
Add the numbers
z4×8
Use the commutative property to reorder the terms
8z4
8z4−6z2−10z2−7z2−5z2
Subtract the terms
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Simplify
8z4−6z2−10z2
Subtract the terms
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Evaluate
−6z2−10z2
Collect like terms by calculating the sum or difference of their coefficients
(−6−10)z2
Subtract the numbers
−16z2
8z4−16z2
8z4−16z2−7z2−5z2
Subtract the terms
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Simplify
8z4−16z2−7z2
Subtract the terms
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Evaluate
−16z2−7z2
Collect like terms by calculating the sum or difference of their coefficients
(−16−7)z2
Subtract the numbers
−23z2
8z4−23z2
8z4−23z2−5z2
Subtract the terms
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Evaluate
−23z2−5z2
Collect like terms by calculating the sum or difference of their coefficients
(−23−5)z2
Subtract the numbers
−28z2
8z4−28z2
Rewrite the expression
4z2×2z2−4z2×7
Solution
4z2(2z2−7)
Show Solution

Find the roots
z1=−214,z2=0,z3=214
Alternative Form
z1≈−1.870829,z2=0,z3≈1.870829
Evaluate
z2×8z2−6z2−10z2−7z2−5z2
To find the roots of the expression,set the expression equal to 0
z2×8z2−6z2−10z2−7z2−5z2=0
Multiply
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Multiply the terms
z2×8z2
Multiply the terms with the same base by adding their exponents
z2+2×8
Add the numbers
z4×8
Use the commutative property to reorder the terms
8z4
8z4−6z2−10z2−7z2−5z2=0
Subtract the terms
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Simplify
8z4−6z2−10z2
Subtract the terms
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Evaluate
−6z2−10z2
Collect like terms by calculating the sum or difference of their coefficients
(−6−10)z2
Subtract the numbers
−16z2
8z4−16z2
8z4−16z2−7z2−5z2=0
Subtract the terms
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Simplify
8z4−16z2−7z2
Subtract the terms
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Evaluate
−16z2−7z2
Collect like terms by calculating the sum or difference of their coefficients
(−16−7)z2
Subtract the numbers
−23z2
8z4−23z2
8z4−23z2−5z2=0
Subtract the terms
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Simplify
8z4−23z2−5z2
Subtract the terms
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Evaluate
−23z2−5z2
Collect like terms by calculating the sum or difference of their coefficients
(−23−5)z2
Subtract the numbers
−28z2
8z4−28z2
8z4−28z2=0
Factor the expression
4z2(2z2−7)=0
Divide both sides
z2(2z2−7)=0
Separate the equation into 2 possible cases
z2=02z2−7=0
The only way a power can be 0 is when the base equals 0
z=02z2−7=0
Solve the equation
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Evaluate
2z2−7=0
Move the constant to the right-hand side and change its sign
2z2=0+7
Removing 0 doesn't change the value,so remove it from the expression
2z2=7
Divide both sides
22z2=27
Divide the numbers
z2=27
Take the root of both sides of the equation and remember to use both positive and negative roots
z=±27
Simplify the expression
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Evaluate
27
To take a root of a fraction,take the root of the numerator and denominator separately
27
Multiply by the Conjugate
2×27×2
Multiply the numbers
2×214
When a square root of an expression is multiplied by itself,the result is that expression
214
z=±214
Separate the equation into 2 possible cases
z=214z=−214
z=0z=214z=−214
Solution
z1=−214,z2=0,z3=214
Alternative Form
z1≈−1.870829,z2=0,z3≈1.870829
Show Solution
