Use the chain rule.
Let u = 25sin²(x), such that dy/dx = dy/du · du/dx


The answer is here. Hope I did help you.
Answer:
She did not use the reciprocal of the divisor.
She added the numerators.
40 dimes is $4.00. you would need $1 in nickles. 2 nickles is 10 cents. so you would need 20 nickles.
10x+160=300
-160 -160
10x=140
divide both sides by 10
x=14
$14