Here's a pattern to consider:
1+100=101
2+99=101
3+98=101
4+97=101
5+96=101
.....
This question relates to the discovery of Gauss, a mathematician. He found out that if you split 100 from 1-50 and 51-100, you could add them from each end to get a sum of 101. As there are 50 sets of addition, then the total is 50×101=5050
So, the sum of the first 100 positive integers is 5050.
Quick note
We can use a formula to find out the sum of an arithmetic series:

Where s is the sum of the series and n is the number of terms in the series. It works for the above problem.
The answer to which is bigger is -5 because it is closer to zero
Answer:

Step-by-step explanation:
<u><em>The complete question is</em></u>
A chef bought $17.01 worth of ribs and chicken. Ribs cost 1.89 per pound and chicken costs 0.90 per pound. The equation 0.90 +1.89r = 17.01 represents the relationship between the quantities in this situation.
Show that each of the following equations is equivalent to 0.9c + 1.89r = 17.01.
Then, explain when it might be helpful to write the equation in these forms.
a. c=18.9-2.1r. b. r= -10÷2c+9
we have that
The linear equation in standard form is

where
c is the pounds of chicken
r is the pounds of ribs
step 1
Solve the equation for c
That means ----> isolate the variable c
Subtract 1.89r both sides

Divide by 0.90 both sides

Simplify

step 2
Solve the equation for r
That means ----> isolate the variable r
Subtract 0.90c both sides

Divide by 1.89 both sides

Simplify

therefore
The equation
is equivalent
The equation is helpful, because if I want to know the number of pounds of chicken, I just need to substitute the number of pounds of ribs in the equation to get the result.