Question

2x-45=y,2y-21=x solve by substitution method

Answer 1

Step-by-step explanation:

2x-45=y

2x-y=45...............(1)

2y-21=x

x - 2y = 21.............(2)

from 1 and 2,

2x-y=45...............(1)

x - 2y = 21.............(2)

by adding both equations,

3x -3y = 66

3( x-y) = 66

x-y = 66/3

x-y = 22.......................(3)

by subtracting 2 by 1,

x+y = 24.......................(4)

by adding equation 3 and 4,

x-y = 22

x+y = 24

therefore,

2x = 46

hence , x= 23

by putting x=23 in equation 3,

23-y = 22

therefore , -y = 22-23

-y = -1

hence , y= 1

therefore, x = 1 and y = 2.