Q2 of 95 Page 68

In the multiplication table made earlier, take a square of nine numbers, instead of four, and mark the numbers at the four corners:

What is the difference of diagonal sums?

MULTIPLICATION TABLE

In this part, we are considering this red square of a multiplication table.

Diagonal sums: 6+20 = 26

10+12 = 22

Difference between diagonal sums = 26 – 22 = 4

Write number like this:

Instead of a square of four numbers, take a square of nine numbers and mark only the numbers at the four corners.

What is the difference of diagonal products? Explain using algebra.

In the multiplication table made earlier, take a square of nine numbers, instead of four, and mark the numbers at the four corners:

What is the difference of diagonal sums?

In the multiplication table made earlier, take a square of nine numbers, instead of four, and mark the numbers at the four corners:

Explain using algebra, why this difference is the same for all such squares.

In the multiplication table made earlier, take a square of nine numbers, instead of four, and mark the numbers at the four corners:

Explain using algebra, why this difference is the same for all such squares.

Questions · 95

4. Identities

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In the multiplication table made earlier, take a square of nine numbers, instead of four, and mark the numbers at the four corners:What is the difference of diagonal sums?