Answer:
The system has "infinitely many solutions; consistent and dependent" ⇒ D
Step-by-step explanation:
A consistent system of equations has at least one solution.
- The consistent independent system has exactly 1 solution
- The consistent dependent system has infinitely many solutions
An inconsistent system has no solution.
In the system of equations ax + by = c and dx + ey = f, if
- a = d, b = e, and c = f, then the system is consistent dependent and has infinitely many solutions
- a = d, b = e, and c ≠ f, then the system is inconsistent and has no solution
- a ≠ d, and/or b ≠ e, and/or c ≠ f, then the system is consistent independent and has exactly one solution
In the given system of equations
∵ r = -5s + 7
∵ r + 5s - 7 = 0
→ Put the equations in the form of equations above
∵ r = -5s + 7
→ Add -5s to both sides
∴ r + 5s = -5s + 5s + 7
∴ r + 5s = 7 ⇒ (1)
∵ r + 5s - 7 = 0
→ Add 7 to both sides
∴ r + 5s - 7 + 7 = 0 + 7
∴ r + 5s = 7
∴ r + 5s = 7 ⇒ (2)
→ By subtracting equations (1) and (2)
∵ (r - r) + (5s - 5s) = (7 - 7)
∴ 0 + 0 = 0
∴ 0 = 0
→ By using rule 1 above
∵ r = r
∵ 5s = 5s
∵ 7 = 7
∴ The system of equation is consistent dependent and has infinitely
many solutions
∴ The system has "infinitely many solutions; consistent and dependent"
