Add 4 to the whole equation
-10 + 4 < 2x < 8 + 4
Simplify
-6 < 2x < 12
Divide the whole equation by 2
-6/2 < x < 12/2
Simplify
<u>-3 < x < 6</u>
Isosceles triangle because it has two equal sides
U = -b + 21 . . . (1)
u = -2b + 30 . . . (2)
Equating (1) and (2),
-b + 21 = -2b + 30
-b + 2b = 30 - 21
b = 9
u = -9 + 21 = 12
Therefore, (b, u) = (9, 12).
Any angle that would be less than 80 degrees would be known to be called an "Acute Angle". Therefore, your correct answer would then be known to be called an Acute Angle.
I hope this helps you!
