Question

If X=9-4root5 then find xsquare

Answer 1

Answer:

$x = 9 - 4 \sqrt{5 } \\ {x }^{2} = {(9 - 4 \sqrt{5} )}^{2} \\ {x}^{2} = {9}^{2} - 2(9)(4 \sqrt{5} ) + {(4 \sqrt{5} )}^{2} \\ {x}^{2} = 81 - 72 \sqrt{5} + 80 \\ {x}^{2} = 81 - 160 + 80 \\ {x}^{2} = 0 \\ \\ \\ hopes \: it \: helps \\ thank \: and \: mark \: as \: brainliest$