1) x * 81 = 729Dividing both sides by 81:x = 729 / 81x = 9
2) x - 640 = 921 / 3x - 640 = 307Adding 640 to both sides:x = 640 + 307x = 947
1) x * 81 = 729
Dividing both sides by 81:
x = 729 / 81
x = 9
2) x - 640 = 921 / 3
x - 640 = 307
Adding 640 to both sides:
x = 640 + 307
x = 947