Question

use the function $y = 5x + 15$ to find the value of $y$ when $x = -4$. $y = \square$

Explanation:

Step1: Substitute x = -4 into the function

We have the function \( y = 5x + 15 \). Substitute \( x = -4 \) into it, so we get \( y = 5\times(-4)+15 \).

Step2: Calculate the value

First, calculate \( 5\times(-4)= -20 \). Then, add 15 to -20: \( -20 + 15=-5 \).

Answer:

\( -5 \)