Question

Celia simplified the expression Negative 4 x (1 minus 3) minus (2 x + 2). She checked her work by letting x = 5 in both expressions. Her work for the original expression is shown below.

Negative 4 x (1 minus 3) minus (2 x + 2) = negative 4 (5) (1 minus 3) minus (2 (5) + 2) = negative 20 (negative 2) minus 12 = 40 minus 12 = 28.


Celia knows that the simplified expression should also equal 28 when x = 5. Which shows Celia’s simpllifed expression?
–6x – 1
–6x + 2
6x + 1
6x – 2

Answer 1

6x − 2

Reason: -4x(1−3) = -4x(−2) = 8x, and 8x − (2x+2) = 6x − 2. Checking x=5 gives 6(5)−2 = 30−2 = 28.