Answer:
Step-by-step explanation:
(21 + 3y) + y = 90
21 + 4y = 90
4y = 69
y = 17.25
x = 21 + 3(17.25)
x = 21 + 51.75
x = 72.75
Answer check:
72.75 + 17.25 = 90
90 = 90 Corrrrrrect !
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