Question
Solve the quadratic equation
Solve using the quadratic formula
Solve by completing the square
Solve using the PQ formula
x1=421−3209,x2=421+3209
Alternative Form
x1≈−5.592624,x2≈16.092624
Evaluate
x(2x−21)=180
Expand the expression
More Steps

Evaluate
x(2x−21)
Apply the distributive property
x×2x−x×21
Multiply the terms
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Evaluate
x×2x
Use the commutative property to reorder the terms
2x×x
Multiply the terms
2x2
2x2−x×21
Use the commutative property to reorder the terms
2x2−21x
2x2−21x=180
Move the expression to the left side
2x2−21x−180=0
Substitute a=2,b=−21 and c=−180 into the quadratic formula x=2a−b±b2−4ac
x=2×221±(−21)2−4×2(−180)
Simplify the expression
x=421±(−21)2−4×2(−180)
Simplify the expression
More Steps

Evaluate
(−21)2−4×2(−180)
Multiply
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Multiply the terms
4×2(−180)
Rewrite the expression
−4×2×180
Multiply the terms
−1440
(−21)2−(−1440)
Rewrite the expression
212−(−1440)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
212+1440
Evaluate the power
441+1440
Add the numbers
1881
x=421±1881
Simplify the radical expression
More Steps

Evaluate
1881
Write the expression as a product where the root of one of the factors can be evaluated
9×209
Write the number in exponential form with the base of 3
32×209
The root of a product is equal to the product of the roots of each factor
32×209
Reduce the index of the radical and exponent with 2
3209
x=421±3209
Separate the equation into 2 possible cases
x=421+3209x=421−3209
Solution
x1=421−3209,x2=421+3209
Alternative Form
x1≈−5.592624,x2≈16.092624
Show Solution
