Roberts number is between 20 and 32. the sum of digits is 10. what is his number

For the digits to have a sum of 10, it has to be one of these:

19, 28, 37, 46, 55, 64, 73, 82, or 91 and the only one in between 20-32 in this case is 28

1

step-by-step explanation:

it's the only multiple of both and the least

the formula of a slope:

from a table we have

substitute:

the slope of f(x) is -1.

the graph of funcfion g(x) is a horizontal line. the slope of a horizontal line is equal 0. therefore the slope of g(x) is 0.

-1 < 0