Answer:
Step-by-step explanation:
Angle sum property of triangle
1) Let the unknown angle = x
x + 43 + 90 = 180
x + 133 = 180
x = 180 -133
[tex]\sf \boxed{\bf x = 47^\circ}[/tex]
2) x + 88 + 30 = 180
x + 118 =180
x = 180 - 118
[tex]\sf \boxed{\bf x = 62^\circ}[/tex]
3) x + 98 + 40 = 180
x + 138 = 180
x = 180 - 138
[tex]\sf \boxed{\bf x = 42^\circ}[/tex]
