[tex]2 {x}^{2} - 9x - 2 +x - 5[/tex]
[tex]2 {x}^{2} - 8x - 7[/tex]
2x² has no other like terms to add or substract with so it stays as is.
(-9x) + x = -8
(-2) - 5 = -7
or
(-2) - (-5) = 3
Watch out for the ones on top. I'm a bit confused about them but those ones are your possible options.
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[tex] {x}^{3} + 27 + x + 3[/tex]
[tex] {x}^{3} + x + 30[/tex]
x³ stays as is and so does x.
27 + 3 = 30
