Kendra owns a restaurant. she charges $3.00 for 2 eggs and one piece of toast, and $1.80 for one egg and one piece of toast. how much does kendra charge for an egg? a piece of toast?

Assume E represents the cost of an egg and T represents the cost of one piece of toast.

We can construct two equations :
2E + T = $3.00 - - - - - (a)
E + T = $1.80 - - - - - (b)

Subtract equation b from a:
E = $1.20 (The price of one egg)

To find out the price of one piece of toast, replace the price of one egg in equation b:
T = $1.80 - $1.20 = $0.60 (The price of one piece of toast)

Hope that helps you