We have two points so we can find the gradient using y1-y2/x1-x2
gradient = 21-27/2-8
= 1
we know the form for any linear equation is y = mx + c
we have m and a point so we can substitute in point (2,21) to find c
21 = 1 x 2 + c
c = 19
therefore, the equation is y = x + 19
Answer:
2 gallons of pure alcohol
Step-by-step explanation:
Let x represent the number of gallons of pure alcohol needed, and create an equation:
4(0.25) + x(1) = (x + 4)0.5
1 + x = 0.5x + 2
x = 0.5x + 1
0.5x = 1
x = 2
So, 2 gallons of pure alcohol should be added.
Answer: 27434
Step-by-step explanation:
Given : Total number of vials = 56
Number of vials that do not have hairline cracks = 13
Then, Number of vials that have hairline cracks =56-13=43
Since , order of selection is not mattering here , so we combinations to find the number of ways.
The number of combinations of m thing r things at a time is given by :-

Now, the number of ways to select at least one out of 3 vials have a hairline crack will be :-

Hence, the required number of ways =27434