Question

x is a positive number. If 9x + 9x+1 + 9x+2 + 9x+3 + 9x+4 + 9x+5 = y, is y divisible by 5? 1) 5 is a factor of x. 2) x is an integer.

Answer 1

Answer:

Step-by-step explanation:

y = 9x+9x+1+9x+2+9x+3+9x+4+9x+5

y = 9x*6+15

y = 54x+15

If x is a factor of 5 then we can say x = 5k, where K is a natural number

y=54*5k+5*3

As we can see everything is a factor of 5 therefore Y is divisible by 5