Solving Linear Equations: Variables on Both Sides — Quiz
Question 6 • *KCPS Algebra I (2027)
What is the justification for the step taken from line 2 to line 3? Line 1: 3 x plus 9 minus 7 x is equal to x plus 10 plus x Line 2: negative 4 x plus 9 is equal to 2 x plus 10 Line 3: negative 6 x plus 9 is equal to 10 Line 4: negative 6 x is equal to 1 Line 5: x is equal to negative 1 sixth
Answer
A
the multiplication property of equality
B
combining like terms on one side of the equation
C
the distributive property
D
the subtraction property of equality
Explanation
From line 2, subtract 2x from both sides: −4x + 9 = 2x + 10 becomes −6x + 9 = 10. Subtracting the same quantity from both sides preserves equality, so the justification is the subtraction property of equality.
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