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Verified Answer :

we have

\(x^{2} -7x=-13\)

Complete the square. Remember to balance the equation by adding the same constants to each side

\(x^{2} -7x+3.5^{2}=-13+3.5^{2}\)

\(x^{2} -7x+12.25=-13+12.25\)

\(x^{2} -7x+12.25=-0.75\)

Rewrite as perfect squares

\((x-3.5)^{2}=-0.75\)

remember that

\(i=\sqrt{-1}\)

Square root both sides

\((x-3.5)=(+/-)\sqrt{-0.75}\)

\((x-3.5)=(+/-)\sqrt{-1*0.75}\)

\((x-3.5)=(+/-)\sqrt{0.75}i\)

\(x1=3.5+\sqrt{0.75}i\)

\(x2=3.5-\sqrt{0.75}i\)

Simplify

\(\sqrt{0.75}=\frac{\sqrt{3}}{2}\)

\(x1=3.5+\frac{\sqrt{3}}{2}i\)

\(x2=3.5-\frac{\sqrt{3}}{2}i\)

therefore

the answer is

\(x1=3.5+\frac{\sqrt{3}}{2}i\)

\(x2=3.5-\frac{\sqrt{3}}{2}i\)

Answer: x =   \(\frac{7±i\sqrt{3}}{2}\) (Ignore the A)

Step-by-step explanation: This is step-by-step using the QF (quadratic formula)

The first step is putting it into SF (Standard Form). Keep in mind the formula for SF is \(ax^{2}\) ± \(bx\) ± c= 0.

You will want to move the -13 from the right side to the left by subtracting it.

x2 – 7x = –13

       +13      +13        (in order to cancel out -13 you will need to use the

---------------------------   opposite operation, in this case adding it.) You will get

\(x^{2}\) - 7x + 13= 0           Now you want to use the QF, which is \(\frac{-b+/- \sqrt{b^{2} -4ac} }{2a}\)

a = 1 (remember that \(x^{2}\) has an invisible 1 in front of it) b = -7 (don"t forget any negative signs with the number(s)) c = 13

\(x=\frac{-(-7)+/-\sqrt{(-7)^{2}-4(1)(13) } }{2(1)}\)    Put everything in parenthesis to make it easier.

                                          Use PEMDAS to solve. Start with \((-7)^{2}\)

\(x = \frac{-(-7)+/-\sqrt{49-4(1)(13)} }{2(1)}\)   Now do all the multiplication under the square root first. Then the -(-7) and lastly the 2(1).

\(x=\frac{7+/-\sqrt{49-52} }{2}\)      (1x13=13 and 4x13= 52) Now do the math in the square root.

\(x=\frac{7+/-\sqrt{-3} }{2}\)   ---  \(x=\frac{7+/-\sqrt{-1}* \sqrt{3} }{2}\)  ----  \(x=\frac{7+/-i \sqrt{3} }{2}\)  There's your answer.

Remember because \(\sqrt{-3}\) is not a real number it has to be broken down into \(\sqrt{-1} *\sqrt{3}\). -1 is = to i. i stands for imagiary.