Answer:
Step-by-step explanation:
when 13 bought we find these inequalities
x + 12y < 7 no
2x + 11y < 7.5 no
3x + 10y < 8 no
4x + 9y < 8.5 no
5x + 8y > 9 yes
When 14 bought we find these inequalities
x + 13y < 7.5 no
2x + 12y < 8 no
3x + 11y < 8.5 no
4x + 10y > 9 yes
Is that a trick question wouldn't it be 20??? I'm confused
5d - 7 = -13
5d = -13 + 7
5d = -6
d = -6/5
I'm not sure what you are trying to convey, but you cannot have more than one digit, so this is imposible
