Question
Solve the following quadratic equation by completing the square method.
$x^2+2 x-5=0$
$x^2+2 x-5=0$
✓
Answer
$x^2+2 x-5=0 $
$ \Rightarrow x^2+2 x+1-1-5=0 $
$ \Rightarrow\left(x^2+2 x+1\right)-(1+5)=0 $
$ \Rightarrow(x+1)^2-6=0 $
$ \Rightarrow(x+1)^2=6 $
$ \Rightarrow x+1=\sqrt{6}$
$ \Rightarrow x+1= \pm \sqrt{6} $
$ \Rightarrow x+1=\sqrt{6} \text { or } x+1=-\sqrt{6} $
$ \Rightarrow x=\sqrt{6}-1 \text { or } x=-\sqrt{6}-1$
$ \Rightarrow x^2+2 x+1-1-5=0 $
$ \Rightarrow\left(x^2+2 x+1\right)-(1+5)=0 $
$ \Rightarrow(x+1)^2-6=0 $
$ \Rightarrow(x+1)^2=6 $
$ \Rightarrow x+1=\sqrt{6}$
$ \Rightarrow x+1= \pm \sqrt{6} $
$ \Rightarrow x+1=\sqrt{6} \text { or } x+1=-\sqrt{6} $
$ \Rightarrow x=\sqrt{6}-1 \text { or } x=-\sqrt{6}-1$
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→Activity :
F.V. = ₹ 100
Number of shares = 300
Market value = ₹ 120
(a) Sum invested = M.V. × No. of shares
$\therefore$ = ⬜ x ⬜
= ₹ 36,000
(b) Dividend per share $=$ F.V. × rate of dividend
= ⬜ x $\frac{⬜}{100} $
= ₹ 7
$\therefore \quad$ Total dividend received $=300 \times 7$
= ₹ ⬜
(c) Rate of return $=\frac{\text { Dividend income }}{\text { Sum invested }} \times 100$
$=\frac{2,100}{36,000} \times 100 $
= ⬜ %
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