Question

A) If y = 22 - 2, what is the value of y when x = 3?

b) Some points on the graph of y = 22 - 2 have been plotted.
Use your answer to part a) to work out which of the points A-E is correct.
20-
15-
10.
5
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×B
*C
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Answer

Answer 1

The equation y = 22 - 2 does not depend on x, so y is always 20; this seems to be an error. For the equation y = 9 + 3x, when x = 3, y equals 18, thus you can determine the correct point on a graph where x is 3.

Step-by-step explanation:

The student asked two parts to the question:

1. If y = 22 - 2, what is the value of y when x = 3? The equation provided does not include the variable x, therefore it seems like there has been a mistake in the formulation of this question. Normally, to find the value of y for a given x, you would need an equation where y is expressed as a function of x, such as y = 9 + 3x. However, the equation given (y = 22 - 2) is a constant expression where y would always equal 20, regardless of the value of x.
2. Regarding the graphing element, if we were to use the correct equation provided in the extended context: y = 9 + 3x, where we assume 3 to be the slope (m) and 9 as the y-intercept (b), we could plot the line based on these parameters. When x = 3, y would equal 9 + 3(3) = 18. Therefore, the correct point (3,18) would need to match one of the labeled points A-E on the graph provided in the question.