Solve for y in the two equations below using substitution.

Mathematics

1 answer:

Solnce55 [7]3 years ago

3 0

Answer:

C. y = -6

Step-by-step explanation:

3x – 6y = 9

–3x + 3y = 9

-3y = 18

y = -6

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The maximum weight that a rectangular beam can support varies jointly as its width and the square of its height and inversely as

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$\bf \textit{now we also know that }~~ \begin{cases} w=\frac{1}{4}\\ h=\frac{1}{3}\\ L=12\\ W=30 \end{cases}\implies 30=\cfrac{~~k\frac{1}{4}\left( \frac{1}{3} \right)^2~~}{12} \\\\\\ 360=\cfrac{k}{36}\implies 12960=k~\hfill \boxed{W=\cfrac{12960wh^2}{L}}$

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