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8 votes
8 votes
Solve the 2x^2 - 5 = 13

User Madper
by
2.5k points

1 Answer

11 votes
11 votes

Answer:

x=3

x=−3

Explanation:

2x^2 - 5 = 13

Subtract 13 from both sides.

2x^2 - 5 - 13 = 0

Subtract 13 from −5 to get −18.

2x^2 - 18 = 0

Divide both sides by 2.

x^2 - 9 = 0

Consider x^2−9. Rewrite x^2−9 as x^2−3^2. The difference of squares can be factored using the rule: a^2−b^2=(a−b)(a+b).

(x−3)(x+3)=0

To find equation solutions, solve x−3=0 and x+3=0.

x=3

x=−3

User KevinOelen
by
3.2k points
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