Question Number 75918 by Master last updated on 21/Dec/19
Answered by Kunal12588 last updated on 21/Dec/19
$${ab}=\mathrm{21} \\ $$$${a}+{c}=\mathrm{10} \\ $$$${c}−{d}=\mathrm{0} \\ $$$${bd}=\mathrm{4} \\ $$$$\Rightarrow \\ $$$${b}=\frac{\mathrm{21}}{{a}} \\ $$$${c}=\mathrm{10}−{a} \\ $$$${d}=\mathrm{10}−{a} \\ $$$${b}=\frac{\mathrm{4}}{\mathrm{10}−{a}} \\ $$$$\frac{\mathrm{21}}{{a}}=\frac{\mathrm{4}}{\mathrm{10}−{a}} \\ $$$$\Rightarrow\mathrm{210}−\mathrm{21}{a}=\mathrm{4}{a} \\ $$$$\Rightarrow{a}=\frac{\mathrm{210}}{\mathrm{25}}=\frac{\mathrm{42}}{\mathrm{5}}=\mathrm{8}.\mathrm{4} \\ $$$${b}=\frac{\mathrm{21}}{\mathrm{8}.\mathrm{4}}=\mathrm{2}.\mathrm{5} \\ $$$${c}=\mathrm{10}−\mathrm{8}.\mathrm{4}=\mathrm{1}.\mathrm{6} \\ $$$${d}=\mathrm{1}.\mathrm{6} \\ $$
Commented by Master last updated on 21/Dec/19
$$\mathrm{thanks} \\ $$