Question

Determinati nr. naturale prime x si y care indeplinesc conditile:
a)9x+5y=60
b)7x-4y=49
c)8x+3y=63


URGENT!!!​

Answer 1

Explicație pas cu pas:

9x+5y=60 =>5y=60-9x => 5y=3(20-3x)=>3|5y

=> 3|y cum y-prim => y=3

9x+15=60 =>9x=45=>x=5 prim

7x-4y=49=>4y=7x-49=>4y=7(x-7)=>7|4y =>

7| y cum y prim => y=7

7x-28=49=>7x=77=>x=11 prim

8x+3y=63=>8x=63-3y=>8x=3(21-y)=>3|8x =>

3| x cum x prim => x=3

24+3y=63=>3y=39=>y=13 prim