Question
Solve the quadratic equation
Solve using the quadratic formula
Solve by completing the square
Solve using the PQ formula
x1=1−7,x2=1+7
Alternative Form
x1≈−1.645751,x2≈3.645751
Evaluate
4(x−1)2=28
Expand the expression
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Evaluate
4(x−1)2
Expand the expression
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Evaluate
(x−1)2
Use (a−b)2=a2−2ab+b2 to expand the expression
x2−2x×1+12
Calculate
x2−2x+1
4(x2−2x+1)
Apply the distributive property
4x2−4×2x+4×1
Multiply the numbers
4x2−8x+4×1
Any expression multiplied by 1 remains the same
4x2−8x+4
4x2−8x+4=28
Move the expression to the left side
4x2−8x−24=0
Substitute a=4,b=−8 and c=−24 into the quadratic formula x=2a−b±b2−4ac
x=2×48±(−8)2−4×4(−24)
Simplify the expression
x=88±(−8)2−4×4(−24)
Simplify the expression
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Evaluate
(−8)2−4×4(−24)
Multiply
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Multiply the terms
4×4(−24)
Rewrite the expression
−4×4×24
Multiply the terms
−384
(−8)2−(−384)
Rewrite the expression
82−(−384)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
82+384
Evaluate the power
64+384
Add the numbers
448
x=88±448
Simplify the radical expression
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Evaluate
448
Write the expression as a product where the root of one of the factors can be evaluated
64×7
Write the number in exponential form with the base of 8
82×7
The root of a product is equal to the product of the roots of each factor
82×7
Reduce the index of the radical and exponent with 2
87
x=88±87
Separate the equation into 2 possible cases
x=88+87x=88−87
Simplify the expression
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Evaluate
x=88+87
Divide the terms
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Evaluate
88+87
Rewrite the expression
88(1+7)
Reduce the fraction
1+7
x=1+7
x=1+7x=88−87
Simplify the expression
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Evaluate
x=88−87
Divide the terms
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Evaluate
88−87
Rewrite the expression
88(1−7)
Reduce the fraction
1−7
x=1−7
x=1+7x=1−7
Solution
x1=1−7,x2=1+7
Alternative Form
x1≈−1.645751,x2≈3.645751
Show Solution
