Two fractions are such that their product is -4 and sum is $$\frac{{ - 32}}{{15}}.$$ Find the two fractions.
A. $$\frac{6}{{15}},\,\frac{{ - 10}}{3}$$
B. $$\frac{6}{5},\,\frac{{ - 10}}{3}$$
C. $$\frac{7}{2},\,\frac{{ - 8}}{7}$$
D. $$\frac{{ - 10}}{7},\,\frac{{14}}{5}$$
Answer: Option B
Solution (By Examveda Team)
$$\eqalign{
& {\text{Let the fractions }}a{\text{ and }}b \cr
& ab = - 4 \cr
& a + b = \frac{{ - 32}}{{15}}{\text{ }}{\text{. }}{\text{. }}{\text{. }}{\text{. }}{\text{. }}\left( 1 \right) \cr
& {\left( {a + b} \right)^2} = {\left( {a - b} \right)^2} + 4ab \cr
& {\left( {\frac{{ - 32}}{{15}}} \right)^2} = {\left( {a - b} \right)^2} + 4\left( { - 4} \right) \cr
& {\left( {a - b} \right)^2} = \frac{{1024}}{{225}} + 16 \cr
& a - b = \sqrt {\frac{{4624}}{{225}}} \cr
& a - b = \frac{{68}}{{15}}{\text{ }}{\text{. }}{\text{. }}{\text{. }}{\text{. }}{\text{. }}\left( 2 \right) \cr
& {\text{Equate equation }}\left( 1 \right){\text{ and }}\left( 2 \right){\text{,}}\,{\text{we get}} \cr
& a = \frac{{18}}{{15}} = \frac{6}{5} \cr
& b = \frac{{ - 100}}{{30}} = \frac{{ - 10}}{3} \cr} $$
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