Multiply the first equation by 5 and add the twice the second equation.
5(0.3x - 0.2y) + 2(0.5x + 0.5y) = 5(4) + 2(85/19)
1.5x - 1.0y + 1.0x + 1.0y = 20 + 170/19
2.5x = 550/19
x = (550/2.5)/19 = 220/19
Substituting this value into the second equation, we get
0.5(220/19) + 0.5y = 85/19
110/19 + 0.5y = 85/19 (eliminate parentheses)
0.5y = -25/19 (subtract 110/19)
y = (-25/0.5)/19 = -50/19 (divide by the y coefficient and evaluate)
The solution is (x, y) = (220/19, -50/19).
5(0.3x - 0.2y) + 2(0.5x + 0.5y) = 5(4) + 2(85/19)
1.5x - 1.0y + 1.0x + 1.0y = 20 + 170/19
2.5x = 550/19
x = (550/2.5)/19 = 220/19
Substituting this value into the second equation, we get
0.5(220/19) + 0.5y = 85/19
110/19 + 0.5y = 85/19 (eliminate parentheses)
0.5y = -25/19 (subtract 110/19)
y = (-25/0.5)/19 = -50/19 (divide by the y coefficient and evaluate)
The solution is (x, y) = (220/19, -50/19).
