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4 years ago

2x squared minus 1 equals 21

Mathematics

2 answers:

dlinn [17]4 years ago

7 0

Answer:

x = √11

Step-by-step explanation:

2x² - 1 = 21

add 1 to both sides

2x² - 1 + 1 = 21 + 1

simplify

2x² = 22

x² = 22 / 2

x = √11

Solnce55 [7]4 years ago

7 0

Answer:

x = √11

Step-by-step explanation

2x² - 1 = 21

negative sign crossing an equal to sign becomes a positive sign

2x² - 1 = 21 + 1

2x² = 22

x² = 22 / 2

x = √11

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2 years ago

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3 years ago

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Step-by-step explanation:

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3 years ago

2x squared minus 1 equals 21​

2x squared minus 1 equals 21