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2y ( x-y) +12=5x where x=3

User Agnese
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1 Answer

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EXPLANATION

Given the expression 2y(x-y) +12=5x , plugging in x=3 into the expression,

2y(3-y) + 12 = 5*3

6y -2y^2 + 12 = 15

Rearranging terms:


-2y^2+6y+12=15

Now, we need to apply the quadratic equation:


\mathrm{For\: a\: quadratic\: equation\: of\: the\: form\: }ax^2+bx+c=0\mathrm{\: the\: solutions\: are\: }
x_(1,\: 2)=(-b\pm√(b^2-4ac))/(2a)
\mathrm{For\: }\quad a=-2,\: b=6,\: c=-3
y_(1,2)=(-6\pm√(6^2-4\left(-2\right)\left(-3\right)))/(2\left(-2\right))

Multiplying terms:


y_(1,2)=\frac{-6\pm\sqrt[]{36-24}}{-4}

Subtracting numbers:


y_(1,2)=\frac{-6\pm\sqrt[]{12}}{-4}

Simplifying:


\mathrm{The\: solutions\: to\: the\: quadratic\: equation\: are\colon}
y=(3-√(3))/(2),\: y=(3+√(3))/(2)

User Misteryes
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