Answer:
[tex]x = \frac{-r - 21}{2}[/tex]
Step-by-step explanation:
Isolate the variable, x. Note the equal sign, what you do to one side, you do to the other. Remember to do the opposite of PEMDAS.
PEMDAS =
Parenthesis
Exponents (& Roots)
Multiplication
Division
Addition
Subtraction
First, subtract 6 from both sides:
2x + 6 (-6) = -r - 15 (-6)
2x = -r + (-15 - 6)
2x = -r + (-21)
2x = - r - 21
Next, divide 2 from both sides:
[tex]\frac{2x}{2} = \frac{-r - 21}{2}[/tex]
[tex]x = \frac{-r - 21}{2}[/tex]
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