Can someone help me solve these Introductory logic proofs

### Recently Asked Questions

- True or False: The point (5, 4) is a solution to this system of equations? 3x + y = 19 2x + 3y = 22

- Given: G = 6.67259 × 10−11 Nm2/kg2 A planet is orbiting a star. Calculate the mass of the star using the fact that the period of the planet is 3.73 × 107 s

- Determine the number of solutions to the system: x + 5y = 4 3x + 15y = 12