Question
Solve the quadratic equation
Solve using the quadratic formula
Solve by completing the square
Solve using the PQ formula
d1=23−15,d2=23+15
Alternative Form
d1≈−0.436492,d2≈3.436492
Evaluate
2(d−3)×3d=9
Multiply
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Evaluate
2(d−3)×3d
Multiply the terms
6(d−3)d
Multiply the terms
6d(d−3)
6d(d−3)=9
Expand the expression
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Evaluate
6d(d−3)
Apply the distributive property
6d×d−6d×3
Multiply the terms
6d2−6d×3
Multiply the numbers
6d2−18d
6d2−18d=9
Move the expression to the left side
6d2−18d−9=0
Substitute a=6,b=−18 and c=−9 into the quadratic formula d=2a−b±b2−4ac
d=2×618±(−18)2−4×6(−9)
Simplify the expression
d=1218±(−18)2−4×6(−9)
Simplify the expression
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Evaluate
(−18)2−4×6(−9)
Multiply
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Multiply the terms
4×6(−9)
Rewrite the expression
−4×6×9
Multiply the terms
−216
(−18)2−(−216)
Rewrite the expression
182−(−216)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
182+216
Evaluate the power
324+216
Add the numbers
540
d=1218±540
Simplify the radical expression
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Evaluate
540
Write the expression as a product where the root of one of the factors can be evaluated
36×15
Write the number in exponential form with the base of 6
62×15
The root of a product is equal to the product of the roots of each factor
62×15
Reduce the index of the radical and exponent with 2
615
d=1218±615
Separate the equation into 2 possible cases
d=1218+615d=1218−615
Simplify the expression
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Evaluate
d=1218+615
Divide the terms
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Evaluate
1218+615
Rewrite the expression
126(3+15)
Cancel out the common factor 6
23+15
d=23+15
d=23+15d=1218−615
Simplify the expression
More Steps

Evaluate
d=1218−615
Divide the terms
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Evaluate
1218−615
Rewrite the expression
126(3−15)
Cancel out the common factor 6
23−15
d=23−15
d=23+15d=23−15
Solution
d1=23−15,d2=23+15
Alternative Form
d1≈−0.436492,d2≈3.436492
Show Solution
