The variable x is 4.
Variables are numbers represented with a letter in an equation.
Therefore, the line RT is a full line segment.
Let's find the variables x
Hence,
RS + ST = RT
Therefore,
3x + 1 + 1 / 2 x + 3 = 18
combine like terms
3x + 1 / 2 x + 1 + 3 = 18
3.5x + 4 = 18
subtract 4 from both sides
3.5x + 4 - 4 = 18 - 4
3.5x = 14
divide both sides by 3.5
3.5x / 3.5 = 14 / 3.5
x = 4
Therefore, the variable x is 4.
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