View Full Version : Simple math driving me crazy.


sevenblu
11-01-06, 04:04 PM
½x² – 5X + 2, whereas x = 2/3

First, I substituted the variables (constants) with 2/3:

½(2/3)² – 5(2/3) + 2

Next, per the order of operations, I solved the exponents:

½(4/9) – 5(2/3) + 2

Then, the multiplication:

2/9 – 10/3 + 2

To make things easier, I found a common denominator:

2/9 – 30/9 + 2

= -28/9 +2

= -3&1/9 + 2

= -1&1/9

My final answer is negative one and one-ninth, however, in the book, the answer to the problem is – (10/9), which is equal to positive one and one ninth.

Absane
11-01-06, 04:08 PM
-1 and 1/9 is the right answer... it's the same thing as -10/9.

However, I am not exactly sure what your question is.

mathman
11-01-06, 04:11 PM
The term 1/9 has a negative sign. It looks like in your mind it has a positive sign.

(comment for sevenblu))

Absane
11-01-06, 04:12 PM
-1&1/9 = -(1 + 1/9) = -(10/9)