Question

Solve the system of equations using substitution. Make sure to show all work and find the value of both x and y

1.

x + y = 4

2x - 3y = 18



2.

2x+ 3y = 8

-3x - 4y = -11


PLEASE SOMEONE HELPPPP PLEASE DUE IN A COUPLE OF MINUTES PLEASEEEEEEE

Answer 1

1) x = 6 and y = -2

2) x = 1 and y = 2

Explanation:

1) x + y = 4...........equ 1

2 x - 3 y = 18 .......... equ 2

x = 4 - y

substituting in equ 2

2 (4 -y) - 3 y = 18

8 - 2 y - 3 y = 18

8 - 5 y = 18

- 5 y = 18 - 8

- 5 y = 10

y = -2

y = -2 put in x = 4 - y

so x = 4 - (-2)

x = 6

therefore x = 6 and y = -2

2) 2 x + 3 y = 8 .....equ 1

-3x -4 y = -11..........equ 2

2x = 8 -3 y

x =( 8 -3 y) ÷ 2

substituting in equ 2

-3{ ( 8 - 3 y) ÷2} - 4 y = -11

- 24 + 9 y- 8 y = -22

- 24 + y = -22

y = 2

If y =2 then x = {8 - (3 × 2)} ÷ 2

x = 1

therefore x = 1 and y = 2