For example:
x+2y=7
6x+7y=2
__________
x=7-2y *
6*(7-2y)+7y=2 **
__________
x=7-2y
42-12y+7y=2
__________
x=7-2y
-5y=-40
__________
x=7-2y
y=8
x=-9
Definition :-
When many plain surfaces combine eachother yielding staright edges ,sharp vertices is called polyhedron .
#1
Yes
- It's cuboid or rectangular prism
#2
No
It has circular shapes ,no sharp edges
#3
No
- It has a sharp vertice but no staright edges .
#4
Yes
- It has flat base and sharp edges also staright edges
Hexgonal pyramid
A=-112 bcs -216 ft is down from sea level and -104 is also down from sea level bcs both values are in minus but -104 is higher than other so you can minus it from -216 the difference is the answer
b=-109
The U and inverted U symbols, ∪ and ∩, are mathematical symbols used to denote union or intersection, respectively. For example, when a rational algebraic equation is graphed, there may be some points where the equation is undefined. Visually, we see it as breaks or discontinuities. We use the ∪ symbol to express union. For example, {-∞,2)∪(4,+∞). That means that the graph passes at all x values except x=3.
The ∩ symbol is used for intersection of two lines, for instance. When equation A and equation B are graphed, they can intersect at points (x,y). It is therefore expressed as: A∩B = (x,y).