Complete the following tasks for this equation: b/7.8 = -2.15. give an estimate for the solution. be sure to explain how you arrived at the estimate, either by showing an equation or in words. solve the equation. show or explain your work. compared to your estimate, is your answer reasonable? explain your answer in complete sentences.

I would estimate this to be about -15, because 7*-2 is about equal to -14 and I am rounding to the nearest 5. 

b/7.8 = -2.15

b = -2.15(7.8)

b = -16.77.

Compared to my estimate, the answer was reasonable, because it was only off by about 2, out of a total of about 17. 2/17 is about a 10% error, which with small numbers as these is reasonable. 

Hope this helps!

For what shape? Rectangular prism?