Simplify the expression-
4+ -9r–1

-9r+3

Step-by-step explanation:

In order to simplify this expression, all you have to do is combine the like terms. However, because there is an addition and a subtraction sign next to each other, we have to multiply them together to find which sign will stay.

Positive x Positive = Positive

Positive x Negative = Negative   <---

Negative x Negative = Positive

Because we know that multiplying a negative sign by a positive sign will give us negative, we have to keep the subtraction sign and remove the addition sign. This leaves us with 4-9r-1. All that is left to do is simplify.

Combine the like terms: 4-1 = 3

-9r+3

Hope this helps!

fourth month

step-by-step explanation:

it is the one with the most keychains.

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.