The addition property of equality is applied to find the value of r which equals 50.
The addition property of equality states that, if a - b = c, then a = c + b.
Given the expression, r - 20 = 30, to find the value of r, apply the addition property of equality as shown below:
Add 20 to both sides
r - 20 + 20 = 30 + 20
r = 50
The value of r using the addition property of equality is: 50.
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