Question

Solve the following system of equations. 0.12x - 0.07y = -1.35 0.4x + 0.8y = 4.8

Answer 1

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