No - It is a function.
A relation which is not a function has more than 1 output for an input.
Caves are formed by the dissolution of limestone. Rainwater picks up carbon dioxide from the air and as it percolates through the soil, which turns into a weak acid. This slowly dissolves out the limestone along the joints, bedding planes and fractures, some of which become enlarged enough to form caves.
Answer:
its the Pentagon, the other shaps have 2 lines if symmetry
3.5*12*11
solve it.............
Answer:
The co-ordinates of the vertex of the function y-9= -6(x-1)^2 is (1, 9)
<u>Solution:</u>
Given, equation is 
We have to find the vertex of the given equation.
When we observe the equation, it is a parabolic equation,
We know that, general form of a parabolic equation is
Where, h and k are x, y co ordinates of the vertex of the parabola.

By comparing the above equation with general form of the parabola, we can conclude that,
a = -6, h = 1 and k = 9
Hence, the vertex of the parabola is (1, 9).