Linear Equations
posted by Wayne .
Solve using the elimination method. If the system has no solution or an infinite number of solutions, state this.
10x  y = 12.5
3x + y = 7

Eq1: 10X  Y = 12.5.
Eq2: 3X + Y = 7.
Add the 2 Eqs and get:
13X + 0 = 19.5.
X = 1.5.
In Eq1, substitute 1.5 for X:
10*1.5  Y = 12.5,
15  Y = 12.5,
Y = 2.5.
Solution set: (X,Y) = (1.5,2.5).