1. **State the problem:** We need to find the value of the angle $j$ given two adjacent angles $49.5^\circ$ and $79.3^\circ$ that together with $j$ form a straight line. 2. **Recall the rule:** Angles on a straight line sum up to $180^\circ$. 3. **Set up the equation:** $$49.5^\circ + j + 79.3^\circ = 180^\circ$$ 4. **Combine known angles:** $$49.5^\circ + 79.3^\circ = 128.8^\circ$$ 5. **Rewrite the equation:** $$128.8^\circ + j = 180^\circ$$ 6. **Solve for $j$:** $$j = 180^\circ - 128.8^\circ$$ 7. **Calculate the value:** $$j = 51.2^\circ$$ **Final answer:** $j = 51.2^\circ$