Answer :
Two Hours
Step By Step :
20-4=16
16/8=2
This is a right angle triangle
So we can use the tangent
tan x = 5/20
tan x= 0.25
x=tan^-1 (0.25)
x= 14.04 degrees
So yes you're correct
For simple integer factors as this one has, you want to find two values for the quadratic in the form ax^2+bx+c. Let the two values be j and k. These two values must satisfy two conditions.
jk=ac=10 and j+k=b=11, so j and k must be 1 and 10.
Now replace bx with jx and kx...
2x^2+x+10x+5 now factor 1st and 2nd pair of terms.
x(2x+1)+5(2x+1)
(x+5)(2x+1)