1. A meal and a dessert together cost $21. The dessert cost $11 less than the meal. What was the cost of the dessert?
I have the equation I just need and explanation I don’t understand why lol I’m trying to get this! Thanks please help will give Brainiest!!

Find the gradient of f(x, y,z)equals=left parenthesis x squared plus y squared plus z squared right parenthesis superscript negative 1 divided by 2 baseline plus ln left parenthesis x right parenthesis x2+y2+z2−1/2+ln(xyz) at the point left parenthesis negative 2 comma 1 comma negative 2 right parenthesis(−2,1,−2).

Find the area of the regular hexagon if a side is 20 cm.

Angela is buying a dress that is on sale for 20% off. if the original price of the dress is $40.00, how much money is angela saving on the dress? a. $0.80 b. $3.20 c. $32.00 d. $8.00