Question

if (1,7) is a point on the graph of y = f(x), which of the following must be on the graph of y = -8f(x)?
choose the correct answer.
(-8,-56)
(1,-56)
(1,7)
(-8,7)

Explanation:

Step1: Substitute \(x = 1\) into \(y=-8f(x)\)

Since \((1,7)\) is on \(y = f(x)\), then \(f(1)=7\).
For \(y=-8f(x)\), when \(x = 1\), \(y=-8\times f(1)\).

Step2: Calculate the value of \(y\)

Substitute \(f(1) = 7\) into \(y=-8\times f(1)\), we get \(y=-8\times7=-56\).

Answer:

\((1, - 56)\)