Question

Complete the following tasks for this equation: 18 =-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.
b. Solve the equation. Show or explain your work.
c. Compared to your estimate, is your answer reasonable? Explain your answer in complete sentences.

Answer 1

To estimate and solve the equation 18 = -2.15, we round -2.15 to the nearest whole number (-2). Then, we isolate the variable by subtracting -2.15 from both sides and find the solution to be 20.15. The estimate of -2 is close to the actual solution, indicating the reasonableness of the answer.

Step-by-step explanation:

a. To give an estimate for the solution, we can round -2.15 to the nearest whole number, which is -2. This is because -2 is the integer closest to -2.15 on the number line.

b. To solve the equation 18 = -2.15, we need to isolate the variable. Subtracting -2.15 from both sides, we get x = 18 - (-2.15) = 18 + 2.15 = 20.15.

c. The estimate of -2 was slightly under the actual solution of 20.15. However, it is still reasonable because -2 is close to 20.15. The estimate helped us understand that the solution is around 20.