The graph of $y = 5^x$ is transformed by a stretch in the $y$-direction, scale factor 5 - AQA - A-Level Maths Mechanics - Question 2 - 2018 - Paper 1

To apply the stretch in the $y$-direction with a scale factor of 5, we multiply the original function by 5. Thus, the transformed equation can be expressed as:

$y = 5 imes 5^x$

This simplifies to:

$y = 5^{x+1}$

However, the correct format in this context should remain as $y = 5 imes 5^x$.