Ok I got anther question what is 10 times 4 my brother says it is 20 but it is 40 who is correct I no I am so who ever answers get 10 points

4x 10 =40

10

10

10

+10

40

40

Step-by-step explanation:

We are attempting to show that ab=ba, where a and b are non-negative integers. Let’s introduce a new equivalence, b+e=a (i.e. e is defined as the difference between a and b; note that if e=0 then the proof becomes trivial. Also note that we assume a≥b; this does not affect our result as the variables are symmetrical). Now we write:

1) ab=∑ai=ib

This is nothing more than stating the definition of b multiplied by a, ie b summed a times. We can also write:

2) ba=b(b+e)

since b+e=a, by our own definition. We now try to show that equation (2) can be rewritten in the form of equation (1). We expand on equation (2) by writing:

3) b(b+e)=∑bi=1(b+e)

This is very similar to what we did regarding equation (1), ie b(b+e) is just (b+e) summed b times. Using some properties of addition, we can transform the right hand side of (3) to read:

4) ∑bi=1(b+e)=∑bi=1b+∑bi=1e

Now what we are going to do is assume the very thing we set out to prove! That is usually a big no-no unless you are using induction, which is basically where this is going.

5) Assume: ∑bi=1e=∑ei=1b

We now substitute (5) back into (4) and proceed:

6) ∑bi=1(b+e)=∑bi=1b+∑ei=1b

The right hand side of (6) can be simplified:

7) ∑bi=1b+∑ei=1b=∑b+ei=1b

Finally, we make use of the fact that b+e=a:

8) ∑b+ei=1b=∑ai=1b

Comparing (8) to (1) yields what we set out to prove:

9) ab=ba

answer: the answer is one of

step-by-step explanation:   we are given to write a proper fraction where the whole is divided into an even number of equal parts less than ten, and an odd number of those parts exist.

an even number less than 10 may be one of 2, 4, 6 or 8. so, the whole may be one of these four evens.

now, an odd number of these parts must exist, so the numerator must be an odd number, one of 1, 3, 5 or 7. it cannot be 9 because then the fraction will become improper.

thus, our fraction may be one of the following

d is correct

step-by-step explanation: