(I will do my best to entirely explain the subject) To understand Positives and Negatives you need to have a number line.
<u>-3 -2 -1 0 1 2 3</u>
Your whole life you have been using positives and negatives when you subtract or add a number. 9 - 2 is really just 9 + -2
With the number line it should be easier to understand that for every single time you add or take away you change the value. The more you take away (Negative numbers, 5 + -6) the farther down the value goes to the left, more towards the negative side (5 + -6 = -1). The same goes for addition (-6 + 9 = 3).
To multiply all you need to do is count how many times you see a negative number. If you see an even number of negatives then the answer will be positive because on the number line you went from one side to the other multiple times, left right left right and all that jazz. Hopefully i made this make more sense to you, if there is anything i need to clarify on please make it known so i can edit my answer.
Phone card = $20
You need to minus 17.92 from 20 = $2.08
$2.08 / 0.13 = how many minutes
= 16
It’s 130°, because 50+50=100 and 2x is equal to the same angel on the direct opposite side so work where you have 50. then the 4 angles should add to 360° and 360-100= 260, then you have to divide 260 by 2 because it has to be equal to both side so then 260/2=130° and to know that it’s correct add 130+130+50+50 and you get 360°!
