Use the (-b + - sqrt( b^2 - 4ac) ) /2a Formula.
a = 1 b= 10 c= 24
so you get .. (x+6 )(x+4) A
-5/8
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If the gradient is -2 that just means we work back the way, the method i use to find the gradient is y^2-y^1/x^2-x^1 so if we sub the variables in that gives us -18-(-8)/3-x so if we add that up we get -10/3-x, so what has to be on the bottom to get -2? in this case it would be -2 so the overall answer would be -10/5 which would give us a slope of -2 when simplified :) hope this helps
Acute would be less than 90 degrees, obtuse is greater than 90 degrees and right is 90 degrees