So, we are given the y intercept, and since we know c is the same as the y value of the y intercept, we know that c=15.
From there we can pick any two of the points given to us to find our a and b.
Let's use (4,17) and (8,23) becase they are whole numbers.
So, with b=0, we can plug it back into the first equation to get:
So our quadratic is 
The answer is 31.9g
The other metal weighs 9.9 grams
Answer:
16 batches are to be made for the party.
Explanation:
Given:
Number of batches for every 9 people= 2
Total number of people attending the party=72
To Find:
The Number of batches required=?
Solution:
Let the number of batches for 72 people be n
So, by cross multiplication method,
2 x 72 = n x 9
9n = 72 x 2
n = 8 x 2
n = 16
Okay so the value of X is 9x^2/7
