Final answer:
To find the output of the function y=(2/3)x-4 for x=21, you substitute 21 into the equation to get y = (2/3)*21 - 4 and solve it to find that y equals 10.
Step-by-step explanation:
To find the output (y) of the function y = (2/3)x - 4 when the input (x) is 21, we substitute 21 for x in the equation and perform the necessary calculations:
- Substitute 21 for x: y = (2/3) × 21 - 4.
- Multiply: y = 2 × 7 - 4.
- Simplify: y = 14 - 4.
- Subtract: y = 10.
The output (y) when the input (x) is 21 is 10.