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I need help with question number 2 and 3. But 2 if I can only get help with one question.

I need help with question number 2 and 3. But 2 if I can only get help with one question-example-1
User Naveen Thunga
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1 Answer

24 votes
24 votes

Number 2:

To solve the quadratic equation by using the factorization method;


x^2-6x+8=0

We note here that the factors of 8 that can also add up to -6 are -4 and -2.

Therefore we'll have;


\begin{gathered} x^2-4x-2x+8=0 \\ (x^2-4x)-(2x+8)=0_{} \\ x(x-4)-2(x-4)=0 \\ \text{Collect like terms and we'll have;} \\ (x-4)(x-2)=0 \end{gathered}

Therefore, we now have;


\begin{gathered} x-4=0,x-2=0 \\ x=4,x=2 \end{gathered}

To solve the quadratic equation by using the quadratic equation formula, we would have;


\begin{gathered} x^2-6x+8=0 \\ \text{The formula is;} \\ x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a} \\ \text{Where;} \\ a=1,b=-6,c=8 \\ x=\frac{-\lbrack-6\rbrack\pm\sqrt[]{(-6^2)-4(1)(8)}}{2(1)} \\ x=\frac{6\pm\sqrt[]{36-32}}{2} \\ x=\frac{6\pm\sqrt[]{4}}{2} \\ x=(6\pm2)/(2) \\ \text{Hence, we now have;} \\ x=(6+2)/(2),x=(6-2)/(2) \\ x=(8)/(2),x=(4)/(2) \\ x=4,x=2 \end{gathered}

Therefore, using the quadratic equation formula, we also have;


x=4,x=2

User Nishat
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