{what is the area of the shaded region of the parallelogram below?}
plshelp!!

Complete the following tasks for this equation: b/7.8=-2.15

a. Give an estimate for the solution. Be sure to explain how you arrived at the estimate, either by showing an equation or in words.

Estimate is b = -17. Since the answer of b divided by 7.8 is -2.15, I know that b should be greater than its double. If we double 7.8 I will get 15.6 so the value should be greater than -15.6 but not so big.

b. Solve the equation. Show or explain your work.

b/7.8 = -2.15, multiply both sides by 7.8 to get

b = (-2.15)*7.8

b= - 16.77

c. Compared to your estimate, is your answer reasonable? Explain your answer in complete sentences.

My estimate is -17 while the computed answer is -16.77. I believe my answer is reasonable since my estimate is just near the computed answer.