If C = x + 6 and D = 3x - 6 + 4x2, find an expression that equals C + 3D in standard form.
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On an airplane there are two seats on the left side and three seats on the right side there are 90 seats o the right side of the plane

Create and solve a linear equation that represents the model, where squares and triangles are shown evenly balanced on a balance beam. assume the weight of a square is 1 unit and the weight of a triangle is unknown.

If a is a nonzero real number then the reciprocal of a is