The answer for number one is d because 7 multiply by5 is 35
The answer for number two is a
24* 80/100 = 24*8/10 = 19.2 is the answer.
9 2/5 - 1 1/3 =
47/5 - 4/3 =
141/15 - 20/15 =
121/15 =
8 1/15 <==
You problem is you don't have any problem. You have a bunch of formulas for the perimeter and area of some shapes.
As for using the formulas, usually you're given all but one of the variables and you can solve for the remaining one.
Notice how the triangle result doesn't have area as a function of a, b and c. That's called Heron's formula and is usually not taught to secondary school students. I don't like to teach it either because Archimedes' Theorem is so much better:
The sides a,b,c and area S of a triangle satisfy

Answer:
- C) The distance is the absolute value of the difference
Step-by-step explanation:
We are interested in the last two columns.
If we compare them we see that each value of the distance column is the absolute value of corresponding value of difference:
- a - b = 1, 5, - 3
- distance = 1, 5, 3
Corect choice is C