Question 678897
x+y=-10
xy=-75
...
x(-10-x)= -75
{{{-10x - x^2 = -75}}}
...
{{{0 = x^2 + 10x - 75}}}
...
{{{0 = (x-5)(x+15)}}}
...
x - 5 = 0, so {{{highlight_green(x = 5)}}}
AND
x + 15 = 0, so {{{highlight_green(x = -15)}}}
.....................
Delighted to help; feel free to email if you have further questions.
HomeworkHelpers@readingboosters.com
-Reading Boosters
Website: www.MyHomeworkAnswers.com 
Wanting for others what we want for ourselves.