Sum of Products Calculator
Our sum of products calculator can help you to calculate the sum of the products of numbers in two series.
The two numbers7 and 3
Check the sum10
Check the product21
Both whole numbers?Yes
Factors asx² − 10x + 21 = (x − 7)(x − 3)
The method
find two numbers with a given sum and product
This is factoring a quadratic
Two numbers with sum s and product p are exactly the roots of x² − sx + p = 0. That is why "find two numbers that multiply to 21 and add to 10" is the same task as factoring x² − 10x + 21 into (x − 3)(x − 7).
A real pair exists only when s² ≥ 4p — the discriminant condition.