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3 votes
3x^2 +6x +18 = 0
solve by completing the sqaure

User SSpoke
by
6.1k points

2 Answers

1 vote

Answer:

x=-1+or-i radical 5

Explanation:

User Johnny Dahdah
by
5.4k points
2 votes

Answer:

=

±

2

4

2

x=\frac{-{\color{#e8710a}{b}} \pm \sqrt{{\color{#e8710a}{b}}^{2}-4{\color{#c92786}{a}}{\color{#129eaf}{c}}}}{2{\color{#c92786}{a}}}

x=2a−b±b2−4ac

Once in standard form, identify a, b and c from the original equation and plug them into the quadratic formula.

3

2

+

6

+

1

8

=

0

3x^{2}+6x+18=0

3x2+6x+18=0

=

3

a={\color{#c92786}{3}}

a=3

=

6

b={\color{#e8710a}{6}}

b=6

=

1

8

c={\color{#129eaf}{18}}

c=18

=

6

±

6

2

4

3

1

8

2

3

x=\frac{-{\color{#e8710a}{6}} \pm \sqrt{{\color{#e8710a}{6}}^{2}-4 \cdot {\color{#c92786}{3}} \cdot {\color{#129eaf}{18}}}}{2 \cdot {\color{#c92786}{3}}}

x=2⋅3−6±62−4⋅3⋅18

2

Simplify

User Ltebean
by
6.1k points