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7-72.

Find the equation in y = ax2 + bx + c form of the parabola that passes through the points (1, 5), (3, 19), and (−2, 29). 7-72 HW eTool (Desmos). Homework Help ✎

Substitute the point (1, 5) into y = ax² + bx + c where x = 1 and y = 5.

Repeat the previous step with (3, 19) and (−2, 29) to create two more equations.

You have created a system of three equations with three variables. Solve the system of equations.
Refer to problem 6-71 for help.

a + b + c = 5
9a + 3b + c = 19
4 − 2b + c = 29

(a, b, c) = (3, −5, 7). Substitute for a, b, and c to find the equation of the parabola.

Use the eTool below to graph the answer.
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