Question

1.4x+3.9y=6.4, 0.2x-1.3y=1.2 solve by substitution method​

Answer 1

Answer:

done x= 5 and y= -2/13

Plzz marks as brainlist

Answer 2

Answer:

1.4x + 3.9y = 6.4

0.2x-1.3y=1.2

multiply by 10 to the both sides of both equations

14x + 39y = 64 ............(1)

2x - 13y = 12 .............(2)

so from equation (1)

x =( 64 - 39y )/14

put this value of in equation (2)

2x - 13y = 12

⟹2(( 64 - 39y )/14) - 13y = 12

⟹((64 - 39y ) / 7)- 13y = 12

⟹(64 - 39 y - 91y) = 84

⟹ -130y = 84 - 64

y = 20 / -130

y = - 2/13

put this value of y in equation (2)

2x - 13y = 12

2x - 13 (- 2/13) = 12

2x + 2 = 12

x =( 12-2)/2

x = 5