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2 years ago

if the sum of a number and seven is doubled, the result is eight less than the number. Find the number

Mathematics

2 answers:

Kipish [7]2 years ago

5 0

Answer:

-22

Step-by-step explanation:

The result is eight less than the number means that

the result = number - 8

( x + 7 ) * 2 = x - 8

=> 2x + 14 = x - 8

=> x = -22

Alexeev081 [22]2 years ago

4 0

Answer: -18

Step-by-step explanation:

Let the number be represented by x.

If the sum of a number and seven is doubled, the result is four less than the number. The expression would be

2(x + 7) = x - 4

We would open the bracket on the left hand side of the equation by multiplying each term inside the bracket by 2. It becomes

2x + 14 = x - 4

Subtracting 14 and x from the left hand side and the right hand side of the equation, it becomes

2x + 14 - 14 - x =x - x - 4 - 14

x = - 18

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