The denarius was a unit of currency in ancient Rome. Suppose it costs the Roman government 10 denarii per day to support 4 legionaries and 4 archers. It only costs 5 denarii per day to support 2 legionaries and 2 archers. Use a system of linear equations in two variables.Can we solve for a unique cost for each soldier?Choose 1 answer:(A) Yes; a legionary costs 1 denarius per day to support, and an archer costs 2 denarii per day to support.(B) Yes; a legionary costs 2 denarii per day to support, and an archer costs 34 denarii per day to support.(C) No; the system has many solutions.(D) No; the system has no solution.
Q. The denarius was a unit of currency in ancient Rome. Suppose it costs the Roman government 10 denarii per day to support 4 legionaries and 4 archers. It only costs 5 denarii per day to support 2 legionaries and 2 archers. Use a system of linear equations in two variables.Can we solve for a unique cost for each soldier?Choose 1 answer:(A) Yes; a legionary costs 1 denarius per day to support, and an archer costs 2 denarii per day to support.(B) Yes; a legionary costs 2 denarii per day to support, and an archer costs 34 denarii per day to support.(C) No; the system has many solutions.(D) No; the system has no solution.
Define Variables: Let's define the variables for the cost to support each type of soldier. Let L be the cost to support a legionary per day, and A be the cost to support an archer per day.
Scenario 1: We are given two scenarios. In the first scenario, it costs 10 denarii to support 4 legionaries and 4 archers. This can be represented by the equation:4L+4A=10
Scenario 2: In the second scenario, it costs 5 denarii to support 2 legionaries and 2 archers. This can be represented by the equation:2L+2A=5
Simplify Equation: We can simplify the second equation by dividing each term by 2, which gives us:L+A=2.5This is a simpler equation that we can use to solve the system.
System of Equations: Now we have a system of two equations:4L+4A=10L+A=2.5We can use the second equation to solve for one of the variables in terms of the other.
Solve for L: Let's solve the second equation for L:L=2.5−ANow we have an expression for L that we can substitute into the first equation.
Substitute into First Equation: Substitute L=2.5−A into the first equation:4(2.5−A)+4A=10Now, distribute the 4:10−4A+4A=10
Canceling Terms: We notice that the terms −4A and +4A cancel each other out, leaving us with: 10=10 This means that the two equations are not independent; they are actually the same equation when simplified. Therefore, the system does not have a unique solution.
No Unique Solution: Since the system does not have a unique solution, we cannot determine the individual costs for a legionary and an archer based on the given information. The correct answer is:(C) No; the system has many solutions.
More problems from Solve a system of equations using substitution: word problems