Answer:
y = 42
Step-by-step explanation:
Since QT is a midsegment then it is half of RS , that is
QT = [tex]\frac{1}{2}[/tex] RS, substitute values
y = [tex]\frac{1}{2}[/tex] (y + 42) ← multiply both sides by 2 to clear the fraction
2y = y + 42 ( subtract y from both sides )
y = 42
