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How do you multiply #(7+2a)(7-2a)#?

Answer 1

See the entire multiplication process below:

To multiply these two terms you multiply each individual term in the left parenthesis by each individual term in the right parenthesis.

#(color(red)(7) + color(red)(2a))(color(blue)(7) - color(blue)(2a))# becomes:

#(color(red)(7) xx color(blue)(7)) - (color(red)(7) xx color(blue)(2a)) + (color(red)(2a) xx color(blue)(7)) - (color(red)(2a) xx color(blue)(2a))#

#49 - 14a + 14a - 4a^2#

We can now combine like terms:

#49 + (-14 + 14)a - 4a^2#

#49 + 0 - 4a^2#

#49 - 4a^2#

#-4a^2 + 49#

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Answer 2

Julia Adams

To multiply (7+2a)(7-2a), you can use the distributive property or the FOIL method, which stands for First, Outer, Inner, Last. Here's how to do it:

First, multiply the first terms: 7 * 7 = 49. Next, multiply the outer terms: 7 * (-2a) = -14a. Then, multiply the inner terms: 2a * 7 = 14a. Finally, multiply the last terms: 2a * (-2a) = -4a^2.

Combine all the terms together: 49 - 14a + 14a - 4a^2. Combine like terms: 49 - 4a^2.

So, the result of multiplying (7+2a)(7-2a) is 49 - 4a^2.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.