Answer:
-1 + 2 = 1
1 + (-2) = -1
-1 - 2 = -3
1 - (-2) = 3
Step-by-step explanation
When you subtract use keep change change
Rule 1 when you add : If the signs are the same add the numbers and take the sign of the bigger number.
Rule 2 when you add : If the signs are different subtract the numbers and take the sign of the bigger number.
I wanted to help you understand and i hope i did that!
30. Answer if u place the equation into a fraction: example 20/8 yellow over red. Next let’s put the other amount into a fraction, we don’t know yellow so for the fraction we will put x: x/18. For our next step we will then cross multiply 20 by 18 and 8 by x getting 8x=360 from there you divide for x getting 45 yellow.
By setting up a system of equations we can easily solve this problem. Let's denote Jane's working hours with x and Jack's working hours with y. Since they don't want to work more than 65 hours, the first equation is x+y=65. The second equation is 14x+7y=770. By solving this system of equation

, we find that y=20 hours, which is Jack's maximum working hours.
You would have $660. The trick for 10% of something is to move the decimal one place to the left. The decimal is “hidden” to the right of the last 0. Add that interest on to get your answer!! Good luck!