Here, we are required to determine which formulas are true;
The correct answers are Choice C and D
Given that; q = r/2(s + t)
To make r the subject of the formula; we have;
r = 2q/(s + t)
To make s the subject of the formula; we have;
s = (2q/r) - t
To make t the subject of the formula: we have;
t = 2q/r - s
Therefore, only choice C and D are correct.
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