Answer:
Step-by-step explanation:
Hello!
x+y+w = 180°
y = 90°
180 = x +x+12+90
180 = 2x+ 102
180 - 102 = 2x
78 =2x
x = 78/2 = 39
x= 39
y=90
W = 39+12 = 51
