Answer:
All Triangles are closed figure polygons that have three straight sides
Step-by-step explanation:
All 2D shapes are plane figures so this one is false. Three right angles are greater than 180 so this is fake. Polygon and closed figures are shapes with three or more closed sides. And triangles have straight sides.
Answer:
5i
Step-by-step explanation:
Using the rule of radicals
×
⇔ 
and
= i
Given

= 
=
×
× 
= 5 ×
× i
= 5i
Answer: B
Step-by-step explanation:
In the systems of equation it already gives you the solution for x which is -2 so all you have to do is substitute -2 into the first equation and solve for y.
y= 2/3x + 3
x= -2
Substitute x for -2
y =
y=
+
y =
so now you have the solution like this 
X - y = 9
x + 2y = 27
You can subtract the top equation from the bottom
3y = 18
y = 6
x = 15
The two numbers are 15 and 6