huh? this does not make sense
Start with

Add 2x to both sides:

Subtract 21 from both sides:

Divide both sides by 5. Since it is positive, we don't have to change the inequality sign:

So, the answer is 
Answer: 5.6
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Work Shown:
cos(angle) = adjacent/hypotenuse
cos(B) = AB/BC
cos(62) = AB/12
12*cos(62) = AB
AB = 12*cos(62)
AB = 5.63365875
AB = 5.6
#4.
4/12 =x/25
x times 12 is 12x
4 times 25 is 100
12x=100
divide 12 by 100 to get 8.3
Answer:
B
Step-by-step explanation:
Use a graphing calculator like desmos and youll find the answer