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I need help solving the simultaneous equation:

x-y=6
xy=4
and you have to give your answer in their simplest surd form.​

User Jjbskir
by
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1 Answer

6 votes

Answer:

Therefore, the solutions to the system of equations are:

x = 3 + √13 and y = -3 + √13

x = 3 - √13 and y = -3 - √13

These are the simplest surd forms of the solutions to the given system of equations.

Explanation:

To solve the system of equations x - y = 6 and xy = 4, we can use the method of substitution.

From the first equation, we can isolate x by adding y to both sides:

x = y + 6

Substituting this expression for x in the second equation, we get:

(y + 6)y = 4

Expanding the equation, we have:

y^2 + 6y = 4

Rearranging the equation, we get:

y^2 + 6y - 4 = 0

To solve this quadratic equation, we can use the quadratic formula:

y = (-b ± √(b^2 - 4ac)) / (2a)

For our equation, a = 1, b = 6, and c = -4. Substituting these values into the quadratic formula, we get:

y = (-6 ± √(6^2 - 4(1)(-4))) / (2(1))

Simplifying the expression, we have:

y = (-6 ± √(36 + 16)) / 2

y = (-6 ± √52) / 2

y = (-6 ± 2√13) / 2

y = -3 ± √13

Now, we can substitute the values of y back into the first equation to find the corresponding values of x:

For y = -3 + √13, x = (-3 + √13) + 6 = 3 + √13

For y = -3 - √13, x = (-3 - √13) + 6 = 3 - √13

User Ryuji
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7.2k points