Answer:
Perimeter of △BDC=Sum of all the sides=BD+DC+CB=15+15+15=45
Step-by-step explanation:
Given ΔABC is an isosceles triangle, thus, AB=BC=x and AC=12,
perimeter of △ABC is=42
⇒x+x+12=42
⇒2x=30
⇒x=15
Thus, AB=BC=15
Now, △BDC is an equilateral triangle therefore BD=DC=BC=x
Since, x=15, therefore BD=DC=BC=15
Now, Perimeter of △BDC=Sum of all the sides=BD+DC+CB=15+15+15=45
Answer:
4.4mm
Step-by-step explanation:
Circumference of circle
2 Pi r
Diameter of coin = 22mm
Therefore the radius = 11mm
Therfroe the outer edge (circumference)
= 2 Pi r
= 2 x Pi x 11
=69.11mm
For the inner edge
Diameter = 5
Radius = 2.5
Therefroe inner edge (circumference)
= 2 Pi r
= 2 x Pi x 2.5
= 15.7mm
The difference is
69.11 - 15.7
=4.4mm
Answer:
56
Step-by-step explanation:
I'm not 100% sure, use my answer at your own risk
If it has rational coefients and is a polygon
if a+bi is a root then a-bi is also a root
the roots are -4 and 2+i
so then 2-i must also be a root
if the rots of a poly are r1 and r2 then the factors are
f(x)=(x-r1)(x-r2)
roots are -4 and 2+i and 2-i
f(x)=(x-(-4))(x-(2+i))(x-(2-i))
f(x)=(x+4)(x-2-i)(x-2+i)
expand
f(x)=x³-11x+20