1. ## Question-2

x,y,z are different counting numbers.

What is the highest value for -2x-5y-3z

2. Originally Posted by johnerdem
x,y,z are different counting numbers.

What is the highest value for -2x-5y-3z

Is 0 a counting number? If so, the answer is 0. Otherwise, put in 1 for each of x, y, and z to get -10.

Counting numbers doesnt include 0. They are: (1,2,3,4,5................)

And also x,y,z are supposed to be different

The answer for the question is -17 on answer key but i dont know how to do

4. Originally Posted by johnerdem
x,y,z are different counting numbers.

What is the highest value for -2x-5y-3z

Ok if the numbers need to be distinct, then you will obviously want to use the smallest numbers, which are 1, 2, and 3. Then substitute in the values for $\displaystyle x, y, z$ that make $\displaystyle -2x-5y-3z$ the closest to zero it can be. Since y has the highest coefficient, you want to put $\displaystyle y = 1$. Similarly, z has the next highest, so put $\displaystyle z = 2$, and finally $\displaystyle x = 3$. Then $\displaystyle -2(3)-5(1)-3(2) = -17.$

5. The answer depends upon which side of the zero argument you come down on.
Counting Number -- from Wolfram MathWorld

If zero is a counting number then the answer is –7. How?

If zero is not a counting number then what is the? Why?