E1.
a) So it says you need an equation for the amount spent and the amount collected. She spends money when she "used $6 worth of yarn for each scarf" and when she "paid $50 to rent a table."
The expression for the yarn is 60x (x representing the yarn per scarf).
And the expression for how much she spent with the table is simply 50, since it's a one-time thing.
So how much she spent in total is 60x + 50.
She collected money when "she sold every scarf for $10".
The expression would be 10x.
The system of equations would be:
y = 60x + 50
y = 10x