Question 186277
The table is for a quadratic equation-
x, y
-3, 0
-2, -7
-1, -8
0, -3
1, ?
Determine the quadratic equation using the information from the table. And solve for '?'. 
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Using the form: ax^2 + bx + c = y solve for a, b, c
c is the y intercept (x=0), notice in the table when x=0, y = -3
therefore we know that c = -3
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Solve for a and b, take the values for x and y from the given table:
;
when x=-3; y=0
(-3^2)a + (-3)b - 3 = 0
9a - 3b = +3
simplify, divide equation by 3:
3a - b = 1
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when x=-1, y=-8
(-1^2)a + (-1)b - 3 = -8
a - b = -8 + 3
a - b = -5
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Use these two equations for elimination 
3a - b = 1
a  - b = -5
---------------subtraction eliminates b, find a
2a = +6
a = 3
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Find b using 3a - b = 1, substitute 3 for a
3(3) - b = 1
9  - b = 1
-b = 1 - 9
-b = -8
b = +8
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The quadratic equation; y = 3x^2 + 8x - 3
You can check to see if this is true
substitute the given x values in the equation, see if it = y
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Regarding the question mark, find y when x = 1"
y = 3(1^2) + 8(1) - 3
y = 3 + 8 - 3
y? = 8
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Did this make sense to you?