How do you solve $x - 5 y = 10$ $x-5y=10$ , $- 2 x + 10 y = - 20$ $-2x+10y=-20$ ?

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Answer 1 · 2015-11-27T23:31:06

$RR$ , all real numbers

Multiply the first equation by $2$ . This give us:

${(2x-10y=20),(-2x+10y=-20):}$

However, when we add these, we get $0+0=0$ .

This means that the lines are the same line, so the answer is $RR$ , or all real numbers.

If we look at the graphs:

$x-5y=10$
graph{x-5y=10 [-10, 10, -5, 5]}

$-2x+10y=-20$
graph{-2x+10y=-20 [-10, 10, -5, 5]}

How do you solve x-5y=10x−5y=10x-5y=10, -2x+10y=-20−2x+10y=−20-2x+10y=-20?