Answer:
3
Step-by-step explanation:
divide the top number by the bottom to always find the constant of proportionality :D
<h3>
Answer: 4/9</h3>
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Work Shown:

The idea is that when we subtract 10x and x, the infinite decimal pattern (the 4s that go on forever) will cancel. That leads to 9x = 4 which solves to x = 4/9
To find a, you need to isolate/get the variable "a" by itself in the equation:
Multiply the inverse of 1/2, which is 2, to get rid of the fraction

a - 7 = 66 Add 7 on both sides to get "a" by itself
a - 7 + 7 = 66 + 7
a = 73