What does the number 1 in the equation mean in this context?

last option at the bottom.

Step-by-step explanation:

we are told that the the equation

y = 0.73x + 1 represents the Length of the spring when a stretch force is applied,

basically y = length of spring and x = force applied.

from the graph, we can see that when stretch force = 0 (i.e x = 0)

the equation becomes y = 1.

That is to say that the spring has a length of 1 inch when stretch force is zero

(which basically is the same as the last option)

the entire expression should be subtracted from 30. to subtract the quantity, distribute the negative sign, which changes the signs on the terms. so, the –2 changes to positive and gets added to 30 instead of subtracted from it.

hope this ! ^w^