Question

$0.8x-0.2y=7\\0.4x+2y=14$
por metodo de reduccion

Answer 1

Explicación paso a paso:

$0.4x + 2y = 14 \: \: \: \: \: \times ( - 2) \\ - 0.8x - 4y = - 28 \\ 0.8 x - 0.2y = 7 \\ - 4.2y= - 21 \\ 4.2y = 21 \\ y = \frac{21}{4.2} = 5 \\ y = 5$

$0.4x + 2y = 14 \\ 0.4x + 2 \times 5 = 14 \\ 0.4x + 10 = 14 \\ 0.4x = 14 - 10 \\ 0.4x = 4 \\ x = \frac{4}{0.4} = 10 \\ x = 10$

$1)0.8x - 0.2y = 0.8 \times 10 - 0.2 \times 5 = 8 - 1 = 7$

$2)0.4x + 2y = 0.4 \times 10 + 2 \times 5 = 4 + 10 = 14$

espero te sirva