Answer :

so we already know what x equals, so just plug it in to the other equation
now we have 4(2y+3)-5y=9
from here, just solve
y=-1
let me know if you have anymore questions :)
ps - Idk if you'd need this but x=1 :)
We solve the system by substitution.

x = 2y + 3
4x-5y = 9

Substituting the value of x in equation no. 2 , we have,

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

8y + 12 - 5y = 9

3y + 12 = 9

3y = 9-12 = -3

thus, 3y = -3

thus, y = -3/3 = -1

thus, y = -1