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The curve y=ax2+bx+c passes through (2,5) (3,12) and (-1,-4).find the equation of the curve

1 Answer

9 votes

Explanation:

You want to first to substitute to form 3 equations.

5=4a+2b+c

12=9a+3b+c

-4=a-b+c

Now solve with whatever way you fell comfortable, I'm going to use elimination.

First eliminate c

7=5a+b

16=8a+4b --> 4=2a+b

Then I'll eliminate b,

3=3a

a=1

Now solve for b and c

7=5+b

b=2

1-2+c=-4

c=-3

Now for the equation:

y=x^2+2b-3

Hope this helps!

User ZAY
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