Can someone help me how to write the equations of this three problems?
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11. 50 +17x = 356 where x = number of months
17x = 306
x =306 / 17 = 18 months answer
12. 3x + 21 = 60
3x = 39 x = $13 answer
13. 15(x - 20) = 375
15x - 300 = 375
15x = 675
x = $45 answer