How do you solve $x + y = 4$ $x + y = 4$ and $9 x + 9 y = 36$ $9x + 9y = 36$ ?

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Answer 1 · 2016-04-14T20:50:59

$y = 4 - x$ $y = 4-x$ for any $x in RR$

These two equations both describe the same line. Any point on the line is a solution, so there are an infinite number of solutions.

For example, given any $x in RR$ , let $y = 4-x$ .

graph{x+y=4 [-10, 10, -1.72, 8.28]}

How do you solve x + y = 4x+y=4x + y = 4 and 9x + 9y = 369x+9y=369x + 9y = 36?