To analyze Joana's conclusion that the quadratic equation \(4x^2 - 4x - 3 = 0\) has no solutions based on her steps, let's examine her work.
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Step 1: Grouping
Joana rewrites the equation as \(4x^2 + 2x - 6x - 3 = 0\). Here, she correctly breaks down the middle term \(-4x\) into \(+2x\) and \(-6x\). -
Step 2: Grouping Terms
She groups the terms as \((4x^2 + 2x) + (-6x - 3) = 0\). This grouping is valid. -
Step 3: Factor Out GCF
Joana's attempt to factor gives:- From the first grouping \(4x^2 + 2x\), she factored out \(2x\) but stated \(x(4x + 2x)\), which is incorrect. The correct factorization should be \(2x(2x + 1)\).
- From the second grouping \(-6x - 3\), she factored out \(-3\) correctly to get \(-3(2x + 1)\).
Her groupings resulted in: \[ 2x(2x + 1) - 3(2x + 1) = 0 \]
At this point, we notice that there is a common factor \((2x + 1)\), which Joana mistakenly claims does not exist. Therefore, she should correctly factor it out:
\[ (2x + 1)(2x - 3) = 0 \]
After this correct factoring, we set each factor to zero to find the solutions:
- \(2x + 1 = 0 \Rightarrow 2x = -1 \Rightarrow x = -\frac{1}{2}\)
- \(2x - 3 = 0 \Rightarrow 2x = 3 \Rightarrow x = \frac{3}{2}\)
Thus, the equation has two solutions.
In conclusion, Joana's assertion that the quadratic has no solutions is incorrect. The correct answer is:
No, because she can still continue the steps even if the two groupings have no shared binomial.