Core Connections Integrated II, 2015
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Core Connections Integrated II, 2015 View details
1. Section 4.1
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Exercise 20 Page 218

Practice makes perfect
a To complete the table, we must substitute each value of x in the function and simplify the right-hand side to find its corresponding y-value.

|c|c|c| [-1em] x & x^2 & y [0.3em] [-0.8em] - 4 & ( - 4)^2 & 16 [0.5em] [-0.8em] - 3 & ( - 3)^2 & 9 [0.5em] [-0.8em] - 2 & ( - 2)^2 & 4 [0.5em] [-0.8em] - 1 & ( - 1)^2 & 1 [0.5em] [-0.8em] 0 & 0^2 & 0 [0.5em] [-0.8em] 1 & 1^2 & 1 [0.5em] [-0.8em] 2 & 2^2 & 4 [0.5em] [-0.8em] 3 & 3^2 & 9 [0.5em] [-0.8em] 4 & 4^2 & 16 [0.5em] We can plot these ordered pairs in a coordinate plane. Then we will connect them with a smooth curve.

b Looking at the graph we made in Part A, we see that the parabola is opening upwards and has a minimum at (0,0). Since the vertex is a minimum or maximum of the parabola, point (0,0) is a vertex.