Expanding and Simplifying the Expression (3x + 5y)² - 30xy = 9x² + 25y²
This problem involves expanding a binomial squared and then simplifying the expression to see if it equals the given result. Let's break it down step-by-step:
Expanding the Binomial
The expression (3x + 5y)² represents the square of the binomial (3x + 5y). We can expand this using the following formula:
(a + b)² = a² + 2ab + b²
Applying this to our expression:
(3x + 5y)² = (3x)² + 2(3x)(5y) + (5y)² = 9x² + 30xy + 25y²
Simplifying the Entire Expression
Now let's substitute the expanded term back into the original expression:
(3x + 5y)² - 30xy = 9x² + 30xy + 25y² - 30xy
Notice that the terms +30xy and -30xy cancel each other out:
= 9x² + 25y²
Conclusion
Therefore, after expanding and simplifying, we find that the expression (3x + 5y)² - 30xy is indeed equal to 9x² + 25y².