MHB Find x and y if x, y are members of real numbers and: (x+i)(3-iy)=1+13i

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To solve for x and y in the equation (x+i)(3-iy)=1+13i, the initial expansion leads to two equations: 3x + y = 1 and -xy + 3 = 13. From the first equation, y can be expressed as y = 1 - 3x. Substituting this into the second equation results in a quadratic equation, which factors to (3x + 5)(x - 2) = 0. The solutions yield the pairs (x, y) = (-5/3, 6) and (2, -5), confirming the calculations.
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Find x and y if x, y are members of real numbers and: (x+i)(3-iy)=1+13i

I first expanded it to give: 3x-yix+3i+y=1+13i
Then I equaled 3x+y=1 and -yx+3=13
But afterwards I do other steps and get the wrong answer.
 
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Your approach and posted work are ok.

To continue,

$$3x+y=1\implies y=1-3x$$

$$3-xy=13\implies xy=-10$$

$$x(1-3x)=-10$$

$$(3x+5)(x-2)=0$$

$$(x,y)=\left(-\frac53,6\right),(2,-5)$$

Does that match your results?
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...

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