Write an equation for the questions:
a) The sum of twice a number and five is the same as the difference between five times the number and sixteen.
2 n + 5 = 5 n-16 or = 16-5n
21 = 3 n or 7 n = 11
n = 7 or n = 11/7
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check
if n = 7
14 + 5 = ??? 35 - 16
19 = 19 check yes
if n = 11/7
22/7 + 5 = ???? 16 - 11/7
22/7+35/7 = ??? 112/7 - 55/7
57/7 = 57/7 yes, check