Question

Suma a două numere este 7,21 , iar diferența lor este 2,17 . Calculați numerel.

Answer 1

a-b=2,17. a+b=7,21, 2a=9,38, a=4,69, b=2,52

Answer 2

[tex]\begin{bmatrix}a+b=7.21\\ a-b=2.17\end{bmatrix} \\ \\ \begin{bmatrix}a+b=\left(\frac{721}{100}\right)\\ a-b=\left(\frac{217}{100}\right)\end{bmatrix} \\ \\ \begin{bmatrix}\frac{721}{100}-b-b=\frac{217}{100}\end{bmatrix} \\ \\ a=\frac{721}{100}-b \\ \\ b=\frac{63}{25} \\ \\ a=\frac{721}{100}-\frac{63}{25}\quad \Rightarrow \quad a=\frac{469}{100} \\ \\ b=\frac{63}{25},\:a=\frac{469}{100} \\ \\ b=2.52,\:a=4.69[/tex]