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3 years ago

How to answer this on descending powers of x please help pretty please

Mathematics

1 answer:

zheka24 [161]3 years ago

4 0

Answer: 25x² - 64

<u>Step-by-step explanation:</u>

(5x + 8)(5x - 8)

= 5x(5x - 8) + 8(5x - 8)

= 25x² - 40x + 40x - 64

= 25x² + 0x - 64

= $\large\boxed{25x^2-64}$

NOTE: descending powers means the biggest exponent goes first, then the next biggest exponent, etc.

For example: x⁴ then x³ then x² then x then the number (which is actually x⁰)

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3 years ago

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