Equation of Straight Line in Plane/Two-Intercept Form/Proof 3

Proof

 * Straight-line-double-intercept-form-Proof-3.png

We have that $\LL$ is passes through the two points $A = \tuple {a, 0}$ and $B = \tuple {0, b}$.

Let $P = \tuple {x, y}$ be an arbitrary point on $\LL$.

We have: