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5 votes
If x+y=12 and xy=27 . find x^3+y^3
pls help with steps ​

User Asad S
by
3.0k points

2 Answers

4 votes

Answer:

x^3 + y^3 = 756

Explanation:

Given that, x+y=12 and xy=27

We know that,


( x + y )^3 = x^3 + y^3 + 3xy(x + y)


12^3 = x^3 + y^3 + 3 * 27 * 12


=> 1728 = x^3 + y^3 + 972


x^3 + y^3 = 1728 - 972


==> x^3 + y^3 = 756

User Yliueagle
by
3.2k points
3 votes

Answer:

Explanation:

use formula

x^3+y^3=(x+y)^3-3*x*y(x+y)

=12^3-3*27(12)

=1728-972

=756

User Marketingexpert
by
3.6k points