Algebra

(3a + b)^2 / (4c - 1),

a = 4;  b = - 2;  c = - 1.

[3 * 4 + (- 2)]^2 / [ 4 * (-1) - 1]=

= [12 - 2]^2 / [- 4 - 1]=

= 10^2 / (- 5) =

= 100 / (- 5) = - 20.

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