Find each product. (8s-3t)(8s+3t)

Question

Accepted Answer

Hey everyone here we are asked to perform multiplication in the given expression where we have the quantity of 10 x minus nine Y times the quantity of 10 X plus nine y. Now here, our first reaction when we are told to multiply this expression is to apply the foil method. But here we can see that we actually have the factored out form of the difference of two squares. So instead of using the foil method, we can actually apply the difference of two squares formula, which tells us that the quantity of a minus B times the quantity of A plus B is equivalent to a squared minus b squared. So year we just need to compare the left hand side of our formula with our given expression to determine the values for A and B. So starting with the value for A. What we can see from our formula that A is the first term in either set of parentheses here. So the first term in our expression is 10 X. Therefore A is just going to be 10 X. And now with B, well we see that B is just going to be the second term in either set of parentheses. So be in our expression is just nine Y. So now with the values for A and B clearly identified, we can go ahead and just substitute them into the right hand side of our formula here. So we see that from our original expression where we had the quantity of X minus nine Y times the quantity of 10 X plus nine Y. What we see from our formula that this expression is equivalent to the quantity of 10 X squared minus the quantity of nine Y squared. So now all that is left to do is simplify our two terms here and we see we have a final answer here of 100 X squared minus 81 Y squared. And with this we have finished our multiplication of our given expression by using or applying the formula for the difference of two squares. Therefore we are left with answer choice. C. Thanks for watching. I hope you found this video helpful and I'll see you again next time.

Find each product. (8s-3t)(8s+3t)

Key Concepts

Difference of Squares Formula

Binomial Multiplication

Exponents and Squaring Terms

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