Question

67. Solve the following pair of linear equations by different algebraical methods and verify that
solution is same in all the methods :
8x + 5y = 9
3x + 2y = 4​

Answer 1

8x + 5y= 9
= 8x+ y = 9- 5
8x+y=4
X+y=4/8
X+y=1/2

Answer 2

by elimination method:

8x+5y=9-----(1)

3x+2y=4-----(2)

multiply by 2 in equation (1) and by 5 in equation (2)

2(8x+5y=9)

5(3x+2y=4)

16x+10y=18

15x+10y=20

Subtract both equation

x=-2 and y =5

BY SUBSITUTION METHOD:

8x+5y=9

8x=9-5y

x=9-5y/8

put x value in equation

3(9-5y/8)+2y=4

27-15y/8+2y=4 (take lcm)

27-15y+16y/8=4

27+y=32

y=5 and x =-2