Question

Brenda sewed a total of 784 buttons on 90 dresses. She sewed 8 or 12 buttons on each dress. how many dresses have 12 buttons on it？please help fast​

Answer 1

The answer is 16
.
12x + 8(90-x) = 784
12x + 720 - 8x = 784
4x = 64
x = 16

16 dresses have 12 buttons