Answer:
C. 14
Explanation:
Add LM and MN
(3x + 5) + (4x + 7)
(4x + 3x) + (5 + 7)
7x + 12
As we know the total is 33
So,
7x + 12 = 33
Subtract 12 from 33, which gives me 21
Now,
7x = 21
To make x alone, divide both sides by 7, and then we will get x = 3
If x = 3
LM = 3x + 5
= (3*3) + 5
= 9 + 5
= 14