Evaluate each expression.

3xy - 2y + 4, when x = -2 and y = -4

2x² - 5x - 12, when x = 5

x² + 3xy - y², when x = -1 and y = -2

3b + 1 - b², when b = -3

a³ - 3a²b + 3ab² - b³, when a = 2 and
b = -2


[tex]3x - 2y + 4 \: when \: x = - 2 \: and \: y = - 4[/tex]
[tex]2 {x }^{2} - 5x - 12 \: when \: x = 5[/tex]
[tex] {x}^{2} + 3xy - {y}^{2} \: when \: x = - 1 \: and \: y = - 2[/tex]
[tex]3b + 1 - {b}^{2} \: when \: b = - 3[/tex]
[tex] {a}^{3} - 3 {a}^{2} b + 3a {b}^{2} - {b}^{3} \: when \: a \: = 2 \: and \: b = - 2[/tex]

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