The aluminum section's area formula solved for h is 
From the complete question, the expression of the area (A) in terms of variables a, b and h is:

Factor out h from the expression on the right-hand side

Divide both sides of the equation by (a - b)

Remove the bracket

Rewrite the above equation as follows:

Hence, the aluminum section's area formula solved for h is 
Read more about change of subject at:
brainly.com/question/9070883
Answer:
17/7, y = 21 * (17/7), 51
Step-by-step explanation:
so to find what x is, we need to find how much it rises in 1 minute. we do that by dividing 17 by 7. we then see that we want to find how much is it filled in 21 minutes. we then multiply (17/7) by 21 to find the y which is 51