The school hiking club has completed 4 out of 5 hikes so far this year. they have hiked 4.6 miles, 3.7 miles, 5.1 miles, and 2.9 miles. if their goal is to hike 20 total miles, how many miles does the last hike need to be?
4.7 miles
3.7 miles
2.7 miles
1.7 miles

They need travel 3.7 miles to reach their goal.

Step-by-step explanation:

The total number of annual miles walked by the club corresponds to the sum of the 5 partial tours, that is:

Total Miles = 4.6 + 3.7 + 5.1 + 2.9 + X, where X represents the number of miles traveled on the last excursion. As you want to travel a total of 20 miles, you have:

Total Miles = 4.6 + 3.7 + 5.1 + 2.9 + X = 20

X = 20 - 4.6 - 3.7 - 5.1 - 2.9 [transposition of terms]

X = 3.7 miles to reach your annual 20 miles goal.

if you was gonna solve for a, a is a   < -12

it would rotate about 180 degrees.