✅ التصحيح المفصّل
الخطوة 1 — نلاحظ العامل المشترك \left(\dfrac{2}{3}x + 1\right)
\( 5\left(\dfrac{2}{3}x + 1\right)\left(2x + 4\right) - \left(\dfrac{2}{3}x + 1\right)^{2} \)
\( = \left(\dfrac{2}{3}x + 1\right)\left[5\left(2x + 4\right) - \left(\dfrac{2}{3}x + 1\right)\right] \)
الخطوة 2 — نبسّط القوس الداخلي
\( 5\left(2x + 4\right) - \left(\dfrac{2}{3}x + 1\right) \)
\( = 10x + (20) - \dfrac{2}{3}x - 1 \)
\( = \dfrac{28}{3}x + (19) \)
\( \left(\dfrac{2}{3}x + 1\right)\left(\dfrac{28}{3}x + 19\right) \)