Solve the following pair of linear equations by the substitution and cross-multiplication
methods :
8x + 5y = 9
3x + 2y = 4

x = -2

y = 5

Step-by-step explanation:

3x + 2y = 4

2y = 4 - 3x

y = 2 - 3/2x

8x + 5y = 9

8x + 5(2 - 3/2x) = 9

8x + 10 - 15/2x = 9

8x - 15/2x + 10 = 9

16/2x - 15/2x = 9 - 10

1/2x = -1

x = -1/1/2

x = -2

3x + 2y = 4

3(-2) + 2y = 4

-6 + 2y = 4

2y = 4 + 6

2y = 10

y = 10/2

y = 5