What does these equation equal to [x+x]+[x+x+x]=blank and [x+x+x]+[x+x+x]=

When turned about its axis of rotation, which shape could have created this three-dimensional object?

To solve the system of equations below, grace isolated the variable y in the first equation and then substituted into the second equation. what was the resulting equation? 3y=12x x^2/4+y^2/9=1

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