Show that (x+5)^2-(x-5)^2=20x

Mathematics

1 answer:

Marta_Voda [28]2 years ago

8 0

Answer:

See Explanation

Step-by-step explanation:

$formula \: to \: be \: used: \\ \boxed{ \boxed{ {a}^{2} - {b}^{2} = (a + b)(a - b)}} \\ \\ {(x + 5)}^{2} - {(x - 5)}^{2} \\ \\ = \{(x + 5) + (x - 5) \} \{(x + 5) - (x - 5) \} \\ \\ = \{x + \cancel5 + x -\cancel 5 \} \{\cancel x + 5 - \cancel x + 5 \} \\ \\ = \{2x \} \{10 \} \\ \\ = 20x \\ \\ \therefore \: {(x + 5)}^{2} - {(x - 5)}^{2} = 20x \\ thus \: proved$

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I need help with this problem please.