If the mass is 20.5 grams, then you have to replace y = 20.5 in the equation.
20.5 = 0.3x - 2
and solve for x, as follows:
20.5 + 2 = 0.3x
22.5 = 0.3x
22.5/0.3 = x
75 = x
The approximate length is 75 cm
3.8m questions
4.9m answers