Answer: In math a mean is the simple mathematical average of a set of two or more numbers.
X²+20=0
x=±√(-80)/2
x=±4i√5/2=2i√5
factorised it is then
(x+2i√5)*(x-2i√5)
See the attached figure
A(4,8) B(0,7) C(4,3)
<span>the line of reflection is x=5
</span>
the reflection is (x,y)-------------------> (10-x,y)
therefore
A(4,8)-----------------> A1(10-4,8)------> A1(6,8)
B(0,7)-----------------> B1(10-0,7)------> B1(10,7)
C(4,3)-----------------> C1(10-4,3)------> C1(6,3)
z/4 + 5 >= 5.5
-5 -5 subtract 5 from both sides
z/4 >= 0.5
x4 x4 times both sides by 4
z >= 2.0