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If the product of a number and -8 is subtracted from the number, the result is 7 more than the number. find the number. Use x for the number.

x-(-8x)=

User JamEnergy
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2 Answers

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You have said that [ x - (-8x) = x + 7 ] .

Note that [ - (-8x) ] = 8x

So the equation may be written as [ x + 8x = x + 7 ] .

Add up the 'x's on the left side: 9x = x + 7

Subtract 'x' from each side: 8x = 7

Divide each side by 8 : x = 7/8


User Halcwb
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x-(-8\cdot x)=x+7\\\\x-(-8x)=x+7\\\\x+8x=x+7\\\\9x=x+7\\\\9x-x=x+7-x\\\\8x=7\\\\8x:8=7:8\\\\x=(7)/(8)
User Sion
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