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What’s the value of x in the equation 3x - y = 18 when y = 27

User Nard
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2 Answers

1 vote

Firstly, we substitute y by 27 to form this equation:

3x - 27 = 18

Equation step-by-step:

3x = -27 = 18 → we take -27 to the right side of the equation

3x = 18 + 27 → we solve for 18 + 27

3x = 45 → we take 3 to the right side of the equation

x = 45 / 3 → we solve for 45 / 3

x = 15 → final answer


Hope it helped,


BioTeacher101

User Michael Reneer
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8.4k points
3 votes
You would have to insert the number into the variable. For example,

3x - 27 = 18
Then, you would isolate the x value (3x).

3x = 18 + 27
Simplify.

3x = 45
Finally, divide both sides by the coefficient.

( 45)/(3) = (3x)/(3)
You end up with

x = 15
User Ewan
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7.7k points