Chapter P - Preliminary Concepts - P.3 - Informal Geometry and Measurement - Exercises P.3 - Page 25: 47

X=102, y =78

We know that the two angles add to 180 degrees. Thus: $$ x+y=180$$ We are also told that: $$ x-y=24$$ Simplifying the second expression: $$ x=y+24$$ Plugging this into the original expression: $$ 2y+24=180 \\ 2y =156 \\ y = 78$$ Thus, it follows that x is equal to: $$ x=y+24 = 78+24 \\ x= 102$$