Answer:
56x² + 2xy+ 3y²
Step-by-step explanation:
81x²+18xy+18xy+4y² - (25x²+10xy+y²) = 56x² + 2xy+ 3y²
It is helpful to become familiar with the rules for secants of a circle.
The product of the numbers on the same chord is the same.
.. 2*x = 5*8
.. x = 20
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The picture is not drawn to scale. (They almost never are.)
