Question

0.4x + 0.3y = 2.5 and 0.5x - 0.3y = 1.I then X = ...​

Answer 1

Answer :

The given system of equations is 0.3x + 0.5y = 0.5 …….i 0.5x + 0.7y = 0.74 …….ii Multiplying i by 5 and ii by 3 and subtracting ii from i we get 2.5y - 2.1y = 2.5 - 2.2 ⇒0.4y = 0.28 ⇒y = 0.28/0.4 = 0.7 Now substituting y = 0.7 in i we have 0.3x + 0.5 × 0.7 = 0.5 ⇒0.3x = 0.50 – 0.35 = 0.15 ⇒x = 0.15/0.3 = 0.5 Hence x = 0.5 and y = 0.7

Answer 2

Answer:

0.3x+0.4y=2.5-----(1)

0.5x0.3y=0.3-------(2)

Multiplying both the equations by 10,

3x+4y=25-----(3)

5x-3y=3-----(4)

Again Multiplying (3) by 5 and (4) by 3,

15x+20y=125------(5)

15x-9y=9------(6)

Subtracting (6) from (5),

29y=116

y=4

Substituting this value of y in (6),

15x-9(4)=9

15x-36+9

15x=45

x=3

Answers:

↪x=3

↪y=4