Answer:
y = 6x² -13x -5
Step-by-step explanation:
(1,-12) (2,-7) (5,80)
y = ax² + bx + c
-12 = a*1² + b*1 + c = a+b+c (1)
-7 = 4a + 2b + c (2)
80 = 25a + 5b + c (3)
(2)-(1): 3a + b = 5 (4)
(3)-(2): 21a + 3b = 87 (5)
(4)*3: 9a + 3b = 15 (6)
(5)-(6): 12a = 72 a = 6
(4) b = -13
(2) c = -5
Answer:
its right
Step-by-step explanation:
0.83 * 100 = 83, so 0.83 = 83/100.
But in case you meant the slightly more interesting repeating decimal, 0.8333...:
Let <em>x</em> denote this number. Then
10<em>x</em> = 8.333...
100<em>x</em> = 83.333...
==> 100<em>x</em> - 10<em>x</em> = 83.333... - 8.333...
==> 90<em>x</em> = 83 - 8 = 75
==> <em>x</em> = 75/90 = 5/6
