168k views
2 votes
Tell whether the point (-9,9) is on the graph of f(x)=[x]. If it is, give the coordinates of another point with the same y-value

1 Answer

5 votes

Final answer:

The point (-9, 9) is not on the graph of the function f(x) = y = 9 + 3x. Substituting x = -9 into the equation gives a y-value of -18. Another point with a y-value of 9 on this line would be the y-intercept, which is (0, 9).

Step-by-step explanation:

The student is inquiring whether the point (-9, 9) lies on the graph of the function f(x) = y = 9 + 3x. To determine if a point is on a graph, we can substitute the x-coordinate into the equation and see if the resulting y-value matches the y-coordinate of the point in question. Substituting x = -9, we obtain y = 9 + 3(-9) = 9 - 27 = -18, which does not match the y-coordinate of the point (-9, 9). Therefore, the point (-9, 9) is not on the graph of the given function. However, for a point to have the same y-value as the given y-coordinate, which is 9, we can set y = 9 in the original equation and solve for x: y = 9 + 3x implies that 9 = 9 + 3x; subtracting 9 from both sides, we have 0 = 3x; therefore, x = 0. Thus, the point with the same y-value of 9 is (0, 9), which is also the y-intercept of the line.

User Lcgodoy
by
7.6k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories