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2 years ago

Solve. −7x = x2 + 12

Mathematics

2 answers:

prisoha [69]2 years ago

6 0

Answer:

x =4 and x= 3

Step-by-step explanation:

the Answer Above is not correct ;/

hope this helps

adelina 88 [10]2 years ago

5 0

Answer:

x = - 4 , x = - 3

Step-by-step explanation:

- 7x = x^2 + 12

Take all terms to one side of equation.

x^2 + 7x + 12 = 0

Find which 2 numbers multiply to give 12 and add to give 7.

a × b = 12

a + b = 7

a = 4

b = 3

Split the middle term using these 2 numbers.

x^2 + 4x + 3x + 12 = 0

Factorise each pair of terms separately.

x ( x + 4 ) + 3 ( x + 4 ) = 0

Bring out common factor of ( x + 4 ) and factorise.

( x + 4 ) ( x + 3 ) = 0

Using the Null factor law, make the expressions in each pair of parentheses equal 0.

x + 4 = 0

x = - 4

AND

x + 3 = 0

x = - 3

THEREFORE:

x = - 4 , x = - 3

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Answer:

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Step-by-step explanation:

I have attached a figure that represents the situation.

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Murrr4er [49]

Answer:

Step-by-step explanation:

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svet-max [94.6K]

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