Answer:
x = -6 and y = 9
Step-by-step explanation:
It is given that,
0.12x - 0.07y = -1.35 -----(1)
0.4x + 0.8y = 4.8 -----(2)
To find the value of x and y
eq(1) * 100 ⇒
12x + 7y = -135 -----(3)
eq(2) /0.4 ⇒
x + 2y = 12 -----(4)
eq(4) * 12 ⇒
12x + 24y = 144 ---(5)
eq(5) - eq(3) ⇒
12x + 24y = 144 ---(5)
12x - 7y = -135 -----(3)
0 + 31y = 279
y = 279/31 = 9
Substitute the value of y in eq(4)
x + 2y = 12 -----(4)
x + 2*9 = 12
x = 12 - 18 = -6
Therefore x = -6 and y = 9
