Answer:
12 meters
Step-by-step explanation:
Given

Required
Determine the measurement when the scale reads 6cm
Represent this scale with x;
Such that:

Equate
and 

Express as fraction

Cross Multiply




Answer:
23x = -115
Step-by-step explanation:
In the substitution method, you must solve for 1 variable in 1 equation to replace it in the other equation. For the system:
2x - 7y = 4
3x + y = -17
Solving for y in the second equation:
y = -17 - 3x
Replacing y in the first equation:
2x - 7(-17 - 3x) = 4
2x + 119 + 21x = 4
23x = -115
This is the new equation after use the substitution method.
1/4(6 + 2c) > 3
0.25 (6+ 2c) > 3
1.5 + 0.5c > 3
0.5c > 1.5
c > 3
Or multiply both sides by 4 to get rid of the 1/4,
6 + 2c > 12
2c > 6
c >3