Integral equation

Integral equations are like algebra equations, but instead of trying to figure out what one number is, we use integrals (special sums) to solve the equation. Imagine you need to know the exact amount of water it took to fill a swimming pool. You would solve an integral equation to figure that out. To do this, think of each bucket of water as an integer. The integral equation will sum up (add together) all the buckets to give you the answer.