First, you combine like terms: x+3x=4x: 12+4x=18-2x
Second, you add the 2x to each side (inverse operation): 12+6x=18
Third, you subtract 12 from 18 to cancel out the 12 (inverse operation): 6x=6
Fourth, you divide each side by 6 to find the value of x
The answer is x=1
Answer:
<em>9*364 - 9*125 - 9*39 = 1,800</em>
Step-by-step explanation:
<em>Mental Calculation</em>
If we detect known patterns in the calculations, we could easily give their results without the use of calculators.
We are given the expression to evaluate:
9*364 - 9*125 - 9*39
The first thing to note is the 9 is a common factor of all terms, thus we take it out:
9*(364 - 125 - 39)
The negative numbers can be easily added
125
+ 39
------------
164
Now our expression is much easier:
9*(364 - 164)
The subtraction of 364-164 is 200, thus the result of the operations is:
9*200. We only need to recall 9*2=18 and add two zeros to get 1,800, thus:
9*364 - 9*125 - 9*39 = 1,800
Answer:
(-3,-6)
Step-by-step explanation:
