Упростите выражение 1)c+72c. 2)34a-a. 3)69n-n-18. 4)25x+37x-17x-x

Упростим:

1) c + 72 * c = с * (1 + 72) = с * 73 = 73 * с; 

2) 34 * a - a = a * (34 - 1) = a * 33 = 33 * a; 

3) 69 * n - n - 18 = n * (69 - 1) - 18 = n * 68 - 18 = 68 * n - 18; 

4) 25 * x + 37 * x - 17 * x - x = x * (25 + 37 - 17 - 1) = x * (25 + 20 - 1) = x * (20 + 19) = x * 39 = 39 * x.