What is 35 * 45?
What is 35 * 45?
Approach: Use (40 - 5)(40 + 5).
1575. 1600 - 25 = 1575.
Follow-up: What is 34 * 46?
Key concepts: difference of squares.
What is 35 * 45?
Approach: Use (40 - 5)(40 + 5).
1575. 1600 - 25 = 1575.
Follow-up: What is 34 * 46?
Key concepts: difference of squares.