Plug in the given point for x y Solve for a Plug in a h k into 2 y a x h k 1

# Plug in the given point for x y solve for a plug in a

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Plug in the given point for (x, y)Solve for a. Plug ina, h, k into 2()ya xhk1.) Write a quadratic equation in vertex form for the parabola shown.2.) Write a quadratic function in vertex form for the function whose graph has its vertex at (2, 1) and passes through the point (4, 5).B. When given the x-intercepts and a third pointPlug in the x-intercepts as p and q into y= a(x p)(Plug in the given point for (x, y)Solve for a. Plug ina, h, k into y= a(x p)(x3.) Write a quadratic function in intercept form for the parabola shown. x q ) q ) 21
B. When given three points on the parabolaLabel all three points as (x, y)Separately, plug in each point into 2yaxbxcYou now have 3 equations with three variables: a, b, cSolve for a, b, and c using elimination (see notes #13). 4.) Write a quadratic function in standard form for the parabola that passesthrough the points ( 5.) Write a quadratic function in standard form for the parabola that passesthrough the points (1, 2), (1, 4) and (2, 1). 22
HW #21: pg. 312 #4-14even Pg. 1013: 1-21 odd, 29-39 all, 43, 48 Chapter 4 Test and Notes Check on Friday 23
Notes #22: Chapter 4 Review To graph a quadratic function, you must FIRST find the vertex (h, k)!!(A) If the function starts in standard form 2yaxbxc1st: The x-coordinate of the vertex, h, = 2ba2nd: Find the y-coordinate of the vertex, k, by plugging the x-coordinate into the function & solving for y.(B) If the function starts in intercept form ()()ya xpxq1st: Find the x-intercepts by setting the factors with x equal to 0 & solving for x.2nd: The x-coordinate of the vertex is half way between the x-intercepts.3rd: Find the y-coordinate of the vertex, k, by plugging the x-coordinate into the function & solving for y. (C) If the function starts in vertex form 2()ya xhk1st: pick out the x-coordinate of the vertex, h. REMEMBER: h will have the OPPOSITE sign as what is in the parenthesis!! : : : 24
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