Linear Equation Word Problems - Examples & Practice

In physics, experiments will often be conducted when the $x$-axis value is nonzero. For example, when you record the relationship between electric potential across a wire and its current, you seldom record its electric potential when the current is $0$, because you assume that the value would naturally be the limit of the V-I curve when I approaches $0$. For this particular experiment, we can actually test when I is $0$ and see that its corresponding potential is $0$. However, in many other experiments you won't be able to measure the corresponding $y$-axis value when the $x$-axis value is 0. What will you do then?