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X^2 - 10x- 3 =0 to the nearest tenth

User Henry Le
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1 Answer

17 votes
17 votes

Given:


x^2-10x-3=0

Find the solution.

Sol:

Use quadratic formula then,


\begin{gathered} ax^2+bx+c=0 \\ \\ x=(-b\pm√(b^2-4ac))/(2a) \end{gathered}

Apply the formula is:


\begin{gathered} x^2-10x-3=0 \\ \\ x=(-(-10)\pm√((-10)^2-4(1)(-3)))/(2(1)) \\ \\ x=(10\pm√(100+12))/(2) \\ \\ x=(10\pm√(112))/(2) \end{gathered}

So the value of x is:


\begin{gathered} x=(10\pm√(112))/(2) \\ \\ x=(10\pm√(28*4))/(2) \\ \\ x=(2(5\pm√(28)))/(2) \\ \\ x=5\pm√(28) \\ \\ x=5\pm5.29 \\ \\ x=0.29,x=10.29 \end{gathered}

So the value of "x" is 0.3 and 10.3

User Smoreno
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