I’m confused on this answer anyone know it?

Mathematics

1 answer:

slamgirl [31]3 years ago

7 0

Answer:

$y=\frac{26}{7},\:x=-\frac{15}{7}$

Step-by-step explanation:

$\begin{bmatrix}4x+5y=10\\ -2x+y=8\end{bmatrix}\\\\\begin{bmatrix}-2\cdot \frac{10-5y}{4}+y=8\end{bmatrix}\\\\$

$-5+\frac{7y}{2}=8\\\\\mathrm{Multiply\:both\:sides\:by\:}2\\-5\cdot \:2+\frac{7y}{2}\cdot \:2=8\cdot \:2\\-10+7y=16\\y=\frac{26}{7}\\$

$\mathrm{For\:}x=\frac{10-5y}{4}\\\mathrm{Subsititute\:}y=\frac{26}{7}\\x=\frac{10-5\cdot \frac{26}{7}}{4}\\\\$

$x=-\frac{15}{7}\\$

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bonufazy [111]

Answer:

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Step-by-step explanation:

the area (A) of a square is calculated as

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