We know that
Triangle Inequality Theorem establishes that the sum of the lengths of any two sides of a triangle<span> is greater than the length of the third side
</span>so
case <span>A. 5M, 11M, 7M
5+11 > 7----> ok
11+7 > 5 ---> ok
5+7 > 11----> ok
case </span><span>B.10 m, 4 m, 5 m
5+4 > 10-----> is not ok
case </span><span>C.8 m, 4 m, 4 m
4+4 > 8----> is not ok
case </span><span>D.6 m,11 m, 5 m
6+5 > 11-----> is not ok
the answer is
</span><span>A. 5M, 11M, 7M</span>
1. C. Concave pentagon
2. A. 1620°
b/c (11 - 2) × 180 = 1620
3. B. 165°
b/c (24 - 2) × 180 ÷ 24 = 165
4. A. 160°
b/c (18 - 2) × 180 ÷ 18 = 160
Answer:
B. (b+3c)+(b+3c)
C. 2(b)+2(3c)
Step-by-step explanation:
we have

Distribute the number 2

Verify each case
case A) 3(b+2c)
distribute the number 3


therefore
Choice A is not equivalent to the given expression
case B) (b+3c)+(b+3c)
Combine like terms


therefore
Choice B is equivalent to the given expression
case C) 2(b)+2(3c)
Multiply both terns by 2


therefore
Choice C is equivalent to the given expression