Answer:
15
Step-by-step explanation:
let r represent red marbles then white = 2r + 5 and total is 20, thus
r + 2r + 5 = 20 ( subtract 5 from both sides )
3r = 15 ( divide both sides by 3 )
r = 5 ← number of red marbles
Thus number of white = 20 - 5 = 15
The answer is A.) 3x-7y and -7y+3x
This is due to "3x" implies the value is positive, or "+3x", and -7y remains -7y.
So, we have 3x-7y and -7y+3x.
I hope this helps!
There is a mistake 9,12,13 is not a right triangle. but 9,12,15 is. IF you use this triangle instead, then the area of the 13,14,15 triangle is the sum of the area of the other two triangles.