{5 х +у =20{2х -у =1

Question

{5 х +у =20
{2х -у =1

Answer 1

{y=20-5x
{2x-20+5x=1
{y=20-5x
{7x=1+20
{y=20-5x
{7x=21
{y=20-5x
{x=3
{y=20-5*3
{x=3
{y=5

Comments

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