Question

the solution of 1.2x + 2.8y = 4 and 2.8x + 1.2y = 4

Answer 1

Answer:

Step-by-step explanation:

1.2x+2.8y= 4

0.3x+ 0.7y=1 (divide by 4)-- <eqn. 1>

Now,

2.8x + 1.2y= 4

0.7x+ 0.3y= 1 (divide by 4)

Y= [1-0.7x] /0.3 -- <eqn 2>

now,

From eqn.1 and eqn.2, we get

0.3x+0.7[(1-0.7x)/0.3]=1

(0.9x+0.7-4.9x)/0.3=1

-4.0x=0.3-0.7

4x=0.4

X= 1/10 or 0.1 --eqn 3

Putting the value of eqn3 in eqn2

We get,

Y=[1-0.7(1/10)] / 0.3

Y=[1-7/10×(1/10)] / (3/10 )

Y=( 1-7/100)×10/3

Y=(100-7)/100 × 10/3

Y= 93 /10 ×1/ 3

Y = 31 /10 or 3.1