Which equation can be used to find the volume of this solid?

A triangular prism. The triangular base has a base of 11 inches and height of 7 inches. The height is 9 inches.
V = 11 times 9 times 7
V = 11 + 9 + 7
V = StartFraction 7 + 9 over 2 EndFraction + 11
V = StartFraction 7 times 11 over 2 EndFraction times 9

I think you mean triangular pyramid. A prism is very very complex.

The formula is 1/3 * base * height.

The formula for a triangle pyramid is shown below V

24

step-by-step explanation:

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.