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Can you help me im not that good at math and its a clear photo

y =___x^2+__x+______

Can you help me im not that good at math and its a clear photo y =___x^2+__x+______-example-1
User Apcelent
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1 Answer

1 vote
  • Vertex/General Form: y = a(x - h)^2 + k, with (h,k) as the vertex
  • (x + y)^2 = x^2 + 2xy + y^2
  • Standard Form: y = ax^2 + bx + c

So before I put the equation into standard form, I'm first going to be putting it into vertex form. Since the vertex appears to be (-1,7), plug that into the vertex form formula:


y=a(x-(-1))^2+7\\y=a(x+1)^2+7

Next, we need to solve for a. Looking at this graph, another point that is in this line is the y-intercept (0,5). Plug (0,5) into the x and y placeholders and solve for a as such:


5=a(0+1)^2+7\\5=a(1)^2+7\\5=a+7\\-2=a

Now we know that our vertex form equation is y = -2(x + 1)^2 + 7.

However, we need to convert this into standard form still, and we can do it as such:

Firstly, solve the exponent:
y = -2(x^2+2x+1) + 7

Next, foil -2(x^2+2x+1):
y = -2x^2-4x-2+7

Next, combine like terms and your final answer will be:
y = -2x^2-4x+5

User Yutao Huang
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