  Flavor SU(3) symmetry implies certain relations among $B$-decay amplitudes to
$\pi\pi$, $\pi K$ and $K {\bar K}$ final states, when annihilation-like
diagrams are neglected. Using three triangle relations, we show how to measure
the weak CKM phases $\alpha$ and $\gamma$ using time-independent rate
measurements only. In addition, one obtains all the strong final-state phases
and the magnitudes of individual terms describing tree (spectator),
color-suppressed and penguin diagrams. Many independent measurements of these
quantities can be made with this method, which helps to eliminate possible
discrete ambiguities and to estimate the size of SU(3)-breaking effects.
