Question
Solve the inequality
Solve the inequality by testing the values in the interval
Solve the inequality by separating into cases
8<x<12
Alternative Form
x∈(8,12)
Evaluate
2(x×7)2(x−8)(x−12)<0
Simplify
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Evaluate
2(x×7)2(x−8)(x−12)
Use the commutative property to reorder the terms
2(7x)2(x−8)(x−12)
Multiply the terms
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Evaluate
2(7x)2
Rewrite the expression
2×49x2
Multiply the numbers
98x2
98x2(x−8)(x−12)
98x2(x−8)(x−12)<0
Rewrite the expression
98x2(x−8)(x−12)=0
Elimination the left coefficient
x2(x−8)(x−12)=0
Separate the equation into 3 possible cases
x2=0x−8=0x−12=0
The only way a power can be 0 is when the base equals 0
x=0x−8=0x−12=0
Solve the equation
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Evaluate
x−8=0
Move the constant to the right-hand side and change its sign
x=0+8
Removing 0 doesn't change the value,so remove it from the expression
x=8
x=0x=8x−12=0
Solve the equation
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Evaluate
x−12=0
Move the constant to the right-hand side and change its sign
x=0+12
Removing 0 doesn't change the value,so remove it from the expression
x=12
x=0x=8x=12
Determine the test intervals using the critical values
x<00<x<88<x<12x>12
Choose a value form each interval
x1=−1x2=4x3=10x4=13
To determine if x<0 is the solution to the inequality,test if the chosen value x=−1 satisfies the initial inequality
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Evaluate
98(−1)2(−1−8)(−1−12)<0
Simplify
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Evaluate
98(−1)2(−1−8)(−1−12)
Subtract the numbers
98(−1)2(−9)(−1−12)
Subtract the numbers
98(−1)2(−9)(−13)
Evaluate the power
98×1×(−9)(−13)
Rewrite the expression
98(−9)(−13)
Rewrite the expression
98×9×13
Multiply the terms
882×13
Multiply the numbers
11466
11466<0
Check the inequality
false
x<0 is not a solutionx2=4x3=10x4=13
To determine if 0<x<8 is the solution to the inequality,test if the chosen value x=4 satisfies the initial inequality
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Evaluate
98×42(4−8)(4−12)<0
Simplify
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Evaluate
98×42(4−8)(4−12)
Subtract the numbers
98×42(−4)(4−12)
Subtract the numbers
98×42(−4)(−8)
Rewrite the expression
98×42×4×8
Transform the expression
98×24×4×23
Multiply the terms with the same base by adding their exponents
98×24+3×4
Add the numbers
98×27×4
Multiply the terms
27×392
Evaluate the power
128×392
Multiply the numbers
50176
50176<0
Check the inequality
false
x<0 is not a solution0<x<8 is not a solutionx3=10x4=13
To determine if 8<x<12 is the solution to the inequality,test if the chosen value x=10 satisfies the initial inequality
More Steps

Evaluate
98×102(10−8)(10−12)<0
Simplify
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Evaluate
98×102(10−8)(10−12)
Subtract the numbers
98×102×2(10−12)
Subtract the numbers
98×102×2(−2)
Rewrite the expression
−98×102×2×2
Multiply the terms
−392×102
Multiply the terms
−39200
−39200<0
Check the inequality
true
x<0 is not a solution0<x<8 is not a solution8<x<12 is the solutionx4=13
To determine if x>12 is the solution to the inequality,test if the chosen value x=13 satisfies the initial inequality
More Steps

Evaluate
98×132(13−8)(13−12)<0
Simplify
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Evaluate
98×132(13−8)(13−12)
Subtract the numbers
98×132×5(13−12)
Subtract the numbers
98×132×5×1
Rewrite the expression
98×132×5
Multiply the terms
490×132
Evaluate the power
490×169
Multiply the numbers
82810
82810<0
Check the inequality
false
x<0 is not a solution0<x<8 is not a solution8<x<12 is the solutionx>12 is not a solution
Solution
8<x<12
Alternative Form
x∈(8,12)
Show Solution
