Answer:
y = (1/4)x² - (5/4)x + 1
Step-by-step explanation:
The x-intercepts of the quadratic equation are simply it's roots.
Thus, we have;
(x + 1) = 0 and (x - 4) = 0
Now, formula for quadratic equation is;
y = ax² + bx + c
Where c is the y intercept.
At y-intercept: (0,1), we have;
At (-1,0), thus;
0 = a(1²) + b(1) + 1
a + b = -1 - - - (1)
At (4,0), thus;
0 = a(4²) + b(4) + 1
16a + 4b = -1
Divide both sides by 4 to get;
4a + b = -1/4 - - - (2)
From eq 1, b = -1 - a
Thus;
4a + (-1 - a) = -1/4
4a - 1 - a = -1/4
3a - 1 = -1/4
3a = 1 - 1/4
3a = 3/4
a = 1/4
b = -1 - 1/4
b = -5/4
Thus;
y = (1/4)x² - (5/4)x + 1
n=2
8+8(8-n)=40+8n (distribute 8 through the parenthesis)
8+64-8n=40-8n (add the numbers)
<em>72-</em>8n=40+8n (move the variable to the left side and change its sign)
<em>72</em><em>-</em>8n+8n=40
-8n+8n=40<em>-72</em> (connect like terms)
-16n = -32 (divide both sides by -16)
<u><em>n=2</em></u>
132cm) so so du Di Di xi Fi vi du du du do go
20 total marbles....7 are green
probability on first draw is 7/20...and since the marble was not replaced, the probability on the second draw is 6/19. And since they cant happen at the same time, we multiply
7/20 * 6/19 = 42/380 which reduces to 21/190
3x+12=5x-21
-5x -5x
-2x + 12 = -21
-12 -12
-2x=-33
x = 16.5
