The value of the expression decreases
Answer:
Step-by-step explanation:
When talking about reflection, we usually mean reflecting across a line, or axis. Reflecting a shape means looking at the mirror image on the other side of the axis. Consider the point (x,y), if you reflect this point across the y-axis you should multiply the x-coordinate by -1, so you get:

For triangle ABC we have:

Therefore, the reflecting points are:

Both the original triangle and the reflected one are shown below.
The temperature at 5 am was -3 degrees
12-15=-3
If we join the points we are gonna end up with a triangle, from there by finding the centroid of the triangle we will get a point which is equidistant from all the three points given in the diagram.
Formula for Centroid:
The area of a triangle can be calculated using the formula
1/2 (base) (height)
Let's substitute our known values, letting x represent the value of the height of the triangle.
16 = 1/2* x* 2x
Let's Simplify!
16 = x^2
Finally, lets take the square root of both sides, to get rid of the exponent on the right side of the equation.
x= positive OR negative 4.
However, because x is equal to the height, we know that it can't be negative, so we know that it is positive 4.
The height of the triangle = 4 inches
The base of the triangle = 2h = 8 inches