y = 2x+5
x+y = 4
Substitute the value of y into the second equation:
x+2x+5 = 4
x+2x = 4-5
3x = -1
Divide both sides by 3 to find the value of x:
x = -1/3
Substitute the value of x into the original equations to find the value of y:
x = -1/3 and y = 4 and 1/3