When the coefficients in (1.3.1) are such that one of the variables does not appear in the...

When the coefficients in (1.3.1) are such that one of the variables does not appear in the equation (for instance, if C = E = F = I = 0), then the graph degenerates to a cylinder with cross sections that are ellipses, parabolas, or hyperbolas. The sides of the cylinder are parallel to the axis labeled with the variable missing from the equation. Sketch graphs of the following degenerate quadric surfaces.

(a)

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(b) y − z2 = 1

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(c) y2 − z2 = 1

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(d) 2x + y2+10y = 0

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(e) 49x2 + 10z2 + 392x + 140z = −1273