Question

The number line shows the distance in meters of two jellyfish, A and B, from a predator located at point X:

A horizontal number line extends from negative 3 to positive 3. The point A is at negative 1.5, the point 0 is labeled as X, and the point labeled B is at 0.5.

Write an expression using subtraction to find the distance between the two jellyfish. (5 points)

Show your work and solve for the distance using additive inverses. (5 points)

Answer 1

for the first part, you'll subtract location B - location A = distance

plugging in values, we have: 0.5 - (-1.5) = distance

(don't simplify anything yet, that's the next step)

for the second part of the question, you can re-write the subtraction as

0.5 + -(-1.5)

using additive inverses. notice how we changed the subtraction to the addition -(-1.5) instead. the negative sign and the subtraction cancel out to get a positive sign

0.5 + 1.5 = 2