Answer:
{(3, -1), (7, 1), (-6, -1), (9, 1), (2, -1)}
Step-by-step explanation:
Any relation having repetitive x-coordinates, is NOT a function.
Unit digit=y
tens digit=x
the number: 10x+y
We suggest this system of equations:
x+y=7
(10y+x)=(10x+y)+9
we solve it by substitution method.
x=7-y
10y+(7-y)=(10(7-y)+y)+9
9y+7=70-10y+y+9
9y+10y-y=70+9-7
18y=72
y=72/18=4
x=7-y
x=7-4=3
number=10x+y=10*3+4=30+4=34
solution: the number: 34
To check:
3+4=7
43=34+9
Answer:
Step-by-step explanation:
9 3/4 = 39/4 mi/m
68 1/4 = 273/4 min
39/4 mutiply by 273/4 = 10647 / 16 mi = 665.4 mi
