Science & Mathematics » Mathematics » How do you solve this problem in the indicated set? 4x-21=18 {integers}?

How do you solve this problem in the indicated set? 4x-21=18 {integers}?

I got as far as x=9.75. Would you round up to 10?

• There are no integer solutions, i.e. no solutions in the "indicated set".
The solution set (restricted to integers) is the empty set.
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• 4x = 39
x = 39 / 4
x = 9•75
x = 10___rounded to nearest integer as you suggest
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• You have :
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4x - 21 = 18

Add 21 to both sides :
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4x - 21 + 21 = 18 + 21

4x = 39

Divide both sides by 4 :
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4x/4 = 39/4

x = 39/4 = 9 3/4 <----------------------------
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• Definitely 10 if it has to be an integer, it would make no sense to round down to 9 so go with 10 all the way
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• 4x-21=18
=>4x=18+21
=>4x=39
=>x=39/4=9.75

When we round it to the nearest tenth, we got 10
So the answer is 10 {integer}
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• 4x-21=18
4x=18+21(Transposing)
4x=39
x=9.75
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• 4x - 21 = 18 ,
4x = 18 + 21 ,
4x = 39 ,
x = 39 / 4 , x = 9 3/4 = 9.75
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• No, no, NO! The equation has no solution in the integers!!
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• 4x-21=18
=>4x=18+21
=>4x=39
=>x=39/4=9.75
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• Simple : we have known real numbers and unknown number,which is X .
By transfer the real number in one side of the equation ,we will have a sequence of a new number.Using the mathematical signs we will determinate value of the X .
In this case :
-21 after transfer to other side will be + 21 ,which mean 4X= 18 +21 ,then 4X = 39
Now by dividing the 39 to 4 39/4=X ,then X is equal with 9.75
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