Answer:
We have that the sum of two numbers is 9
this can be written as:
x + y = 9
where x is the larger number.
Now we want to write:
"the difference between one more than the larger number and twice the smaller number"
First, remember that the difference between A and B is:
A - B
Then "the difference between one more than the larger number and twice the smaller number"
is:
"one more than the larger number" = ( x + 1)
"twice the smaller number" = 2*y
the difference between these is:
(x + 1) - 2*y
Now we can simplify:
We know that:
x + y = 9
then:
y = 9 - x
replacing that in the equation:
(x + 1) - 2*y
we would get:
x + 1 - 2*(9 - x)
x + 1 -18 + 2x
(x + 2x) + (1 - 18)
3x - 17
This means that we can write:
"the difference between one more than the larger number and twice the smaller number"
as: 3x - 17