Okay, first of all, you are probably stuck and don't understand what an exterior angle is. I don't know how to explain it but the exterior angle in this case is ∠DAB.
<h2>∠DAB = ∠ABC + ∠BCA</h2><h2> = 90° + 62°</h2><h2>= 152°</h2><h2 /><h2>They said that the exterior angle was instead 128 degrees. This means that now the sum of the angles of B and C are 152 degrees, or, 152 - 128 = 34 degrees greater.</h2>
3x+5=2x-10
-2x -2x
X+5=-10
-5 -5
X=-15
3(-15)+y=5
-45+y=5
+45 +45
y=50
2(-15)-y=10
-30-y=10
+30 +30
-y=40
Divide by -1 on both sides
y=-40
Area of rectangle=> L•l= 8•5= 40 in²
Area of the triangle=> (b•h)/2= (8•3)/2= 24/2= 12 in²
Area of the shadowed surface is 40-12= 28 in²
