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Can someone helpp pls

Can someone helpp pls-example-1
User Quirimmo
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1 Answer

4 votes

Answer:

Explanation:

You have to solve this as a system. We have 3 coordinates given; the first 2 are given as zeros of the quadratic, the 3rd one is given as a regular coordinate. The zeros of a quadratic are where the y values of a coordinate are 0's because the x-intercepts of a quadratic (aka zeros) exist where y = 0. We use each of those points in the standard form of a quadratic to solve for a, b, and c. First, (0, 0):


0 = a(0)^2+b(0)+c which gives us that c = 0. We'll use that value of c as we move forward with the problem. Next we'll use (3, 0):


0=a(3)^2+b(3)+0\\0 =9a+3bHold that thought for a minute or 2. Next we'll use the coordinate (1, 6):


6=a(1)^2+b(1)+0\\\\6=a+b Now we have a system that we can solve using either substitution or elimination for a and b. I used elimination:

6 = a + b

0 = 9a + 3b and multiply the top equation by -3:

-18 = -3a - 3b

0 = 9a + 3b

so

-18 = 6a and

a = -3. Now back solve for b:

6 = -3 + b so

b = 9 and our quadratic is


y=-3x^2+9x+0 or just


y=-3x^2+9x

User John Montgomery
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4.0k points