SOLUTION: What is an equation for a parabola if the vertex is (0,1) and the endpoints are (-1,2) and (1,2)

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Question 1078920: What is an equation for a parabola if the vertex is (0,1) and the endpoints are (-1,2) and (1,2)
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The general equation is:
+y+=+a%2Ax%5E2+%2B+b%2Ax+%2B+c+
You are given 3 points:
(-1,2), (1,2) and the vertex, (0,1)
-----------------------------------
The x-value of the vertex is:
+x%5Bv%5D+=+-b%2F%282a%29+
+0+=+-b%2F%282a%29+
+b+=+0+
----------------------------
So I have:
+y+=+a%2Ax%5E2+%2B+0%2Ax+%2B+c+
+y+=+a%2Ax%5E2+%2B+c+
--------------------------
(-1,2)
+2+=+a%2A%28-1%29%5E2+%2B+c+
+2+=+a+%2B+c+
(1,2)
+2+=+a%2A1%5E2+%2B+c+
+2+=+a+%2B+c+
---------------------------
(0,1)
+1+=+a%2A0%5E2+%2B+c+
+1+=+c+
---------------------------
+2+=+a+%2B+c+
+2+=+a+%2B+1+
+a+=+1+
---------------------------
+a+=+1+
+c+=+1+
+y+=+x%5E2+%2B+1+
----------------------------
Here's the plot:
+graph%28+400%2C+400%2C+-5%2C+5%2C+-5%2C+5%2C+x%5E2+%2B+1+%29+