A: If all coins are quarters, she'd require 40 quarters. That is because 4 quarters equal a dollar, so I multiplied that by 10 to get the value of 10 dollars. If all coins are dimes, the amount of dimes would be 100, because 10 dimes equal a dollar, so I multiplied that by 10 as well.
B: An equation that'd probably work is 0.25x + 0.10y = $10
I've used those values because x representing quarters meant I had to multiply by it's value, .25 cents. Same goes for dimes.
C, I don't know how to show a graph here, so I'm going to assume you know how to graph.
D: Also requires the graph, but I can think of x = 20, y = 50. You can do it!
