Avg of 7 numbers = 9
Total of 7 numbers will be = 9 * 7 = 63
Avg of 3 of them is = 5
Total of those 3 will be = 3 * 5 = 15
Therefore the total of other 4 = 63 - 15 = 48
Ergo , avg of them = 48 / 4 = 12
Answer is 12
hope this helps!
D. y = 3x + 2
Check (-4, -10)
-10 = 3(-4) + 2
-10 = -12 + 2
-10 = -10 :)
Check (-3, -7)
-7 = 3(-3) + 2
-7 = -9 + 2
-7 = -7 :)
Check (-2, -4)
-4 = 3(-2) + 2
-4 = -6 + 2
-4 = -4 :)
Check (-1, -1)
-1 = 3(-1) + 2
-1 = -3 + 2
-1 = -1 :)
Check (0, 2)
2 = 3(0) + 2
2 = 0 + 2
2 = 2 :)
it has 2 equal sides and 1 unequal side
Easy question.
So, the slope is -x and the y-intercept is at -4.
y = -x - 4
Use this equation and you will find:
y = -2 - 4
y = -6
Answer: (2, -6)
I would think that all but one point would be on the line. One way to approach this problem is to find the equation of the line based upon any two points chosen at random, and then determine whether or not the other points satisfy this equation. Next time, would you please enclose the coordinates of each point inside parentheses: (2.5,14), (2.25,12), and so on, to avoid confusion.
14-12
slope of line thru 1st 2 points is m = ---------------- = 2/0.25 = 8
2.50-2.25
What is the eqn of the line: y = mx + b becomes
14 = (8)(2.5) + b; find b:
14-20 = b = -6. Then, y = 8x - 6.
Now determine whether (12,1.25) lies on this line.
Is 1.25 = 8(12) - 6? Is 1.25 = 90? No. So, unless I've made arithmetic mistakes, (1.25, 5) does not lie on the line thru (2.5,14) and (2.25,12).
Why not work this problem out yourself using my approach as a guide?
