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

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Answer 1 · 2016-06-08T21:43:06

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

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

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

To find the $x$ $x$ coordinate

$y = y$ $y = y$

$2 x + 4 = - x - 11$ $2x+4 =-x-11$

$2 x + x = - 4 - 11$ $2x+ x=-4-11$

$3 x = - 15$ $3x= -15$

$x = - 5$ $x=-5$

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

$y = 2 x + 4$ $y=2x+4$

$y = 2 (- 5) + 4$ $y=2(-5)+4$

$y = - 6$ $y=-6$

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

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