Question

Solve the following linear equation by substitution method

2x + 0.3y = 1.3 , 4x + 5y = 2.3

Answer 1

refer the image for answer
hope this helps;)

Answer 2

2x + 0.3y = 1.3

2x + 3y/10 = 13/10

( 2x + 3y )/10 = 13/10

2x + 3y = 13

3y = 13 - 2x



y=(13-2x)/3 ------(1)

0.4x+0.5y=23______(2)

again 4x+5y=23 ----(2)

substituting the value of y from (1) in (2)

4x+5{(13-2x)/3}=23

4x+65/3-10x/3=23

4x-10x/3=23-65/3

(12x-10x)/3=(69-65)/3

12x-10x=69-65

2x=4

x=2

substitute the value of x in any equation to get the value of y

y=3

thus, x=2 y=3