Answer:
y =52
Step-by-step explanation:
We know that the angles 4x and 5x make a straight line
4x+5x = 180
9x = 180
Divide by 9
9x/9 = 180/9
x = 20
The three angles of a triangle make 180
y + 48 +4x = 180
y + 48+4(20) =180
y + 48 +80 = 180
Combine like terms
y +128 = 180
Subtract 128 from each side
y + 128-128 = 180-128
y =52
