The opposite of his number is positive.
The missing blank should be 1x
Answer:
b=2A/h-a
Step-by-step explanation:
A=1/2h(a+b)
Multiplying by 2
2A=h(a+b)
Dividing by h
2A/h=a+b
Subtracting a
2A/h-a =b
b=2A/h-a
Given :
A bag contains 120 marbles. Some are red and the rest are black. There are 17 red marbles for every 3 black marbles.
To Find :
How many red marbles are in the bag.
Solution :
Let, number of red and black marbles are x and y respectively.
So, x + y = 120 ....1)
Now, it is given that there are 17 red marbles for every 3 black marbles.
So, 3x = 17y ....2)
Putting value of x from equation 2) to equation 1), we get :
Therefore, the number of red and black marbles are 102 and 18 respectively.