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Find the product (4x-5y)^2

User Lambder
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1 Answer

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To find the product of (4x-5y)^2,
we can rewrite the problem as:
(4x-5y)(4x-5y) (two times because it is squared)

Now, time to use that old method we learned in middle school:
FOIL. (Firsts, Outers, Inners, and Lasts)

FOIL can help us greatly in this scenario.
Let's start by multiplying the 'Firsts' together:
4x * 4x = 16x^2

Now, lets to the 'Outers':
4x * -5y = -20xy

Next, we can multiply the 'Inners':
-5y * 4x = -20xy

Finally, let's do the 'Lasts':
-5y * -5y = 25y^2

Now, we can take the products of these equations from FOIL and combine like terms. We have: 16x^2, -20xy, -20xy, and 25y^2.
-20xy and -20xy make -40xy.

The final equation (product of (4x-5y)^2) is:
16x^2 - 40xy + 25y^2

Hope I helped! If any of my math is wrong, please report and let me know!
Have a good one.
User Jdehaan
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8.3k points