Question

7 · 15 can be written as _____.

5(7 + 10)
10(7 + 5)
7(10 + 5)

Answer 1

For the answer to the question above, 
An easy trick can be to just find the product of 15*7. Then with that product see which product equals to the ones written on the answer choices.

the answer is 7(10+5)
I hope my answer helped you.

Answer 2

Answer:

7.15 can be written as 7.(10+5)

Step-by-step explanation:

In this particulary case, we want to write one of the factor from the product as sum of two other numbers. Take into account whether of the factor of the expression we choose, its will have to be the same quantity. For example, in the first expression:

5.(7+10)

The first factor 5 is different two both of the factors from the original expression. Thus 5.(7+10) cant be the answer.

In the second expression:

10.(7+5)

We find  the same problem, 10 is different two both of the factors from the original expression. Thus 10.(7+5) cant be the answer.

The last option:

7.(10+5)

We find that the factor 7 and 10+5 are equals to the factor in the original expression. Therefore 7.(10+5) is the correct expression.