What is the point of intersection of the lines $y = 2x + 4$ and $x + y = -11$ ?

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Answer 1 · 2016-06-08T21:43:06

The straight lines intersect at $(-5,-6)$

At the point of intersection, of two lines have the same $x$ and $y$ coordinates that satisfy the two equations:

$y=2x+4 and " y=-x-11$

To find the $x$ coordinate

$y = y$

$2x+4 =-x-11$

$2x+ x=-4-11$

$3x= -15$

$x=-5$

Use any of the two equations to find a value for $y$

$y=2x+4$

$y=2(-5)+4$

$y=-6$

So the two lines intersect at $(-5,-6)$

What is the point of intersection of the lines y = 2x + 4y = 2x + 4 and x + y = -11x + y = -11?