7x^2-y^3= 8 a) implicit differentiation
b) Solve the equation explicitly for y and differentiate to get
y ′ in terms of x.
c) Check that your solutions to parts (a) and (b) are consistent by substituting the expression for y into your solution for part (a).

answer:

total cost for tiles and paints is $924.  

step-by-step explanation:

we have been given that a community hall is in the shape of a cuboid. the hall is 40m long 15m high and 3m wide.

the paint will be required for 4 walls and ceiling.

let us find area of walls and ceiling.

therefore, the area of walls and ceiling is 1410 square meters.

given: cost for 10 litre of paint is $10 and 10 litre paint covers 25 square meter. therefore,

therefore, the total painting cost is $564.

tiles will be required for floor. let us find the area of floor.

given: 1m squared floor tiles costs $3. so,

therefore, the total tiles cost is $360.

now let us find combined total cost of tiles and paint.

therefore, the combined total cost of tiles and paint is $924.

they charge the same amount at 20 minutes.

step-by-step explanation:

i believe a. 12x≥120 is the answer

i think this is a open ended question but i agree with other guy who said you should ask it at english section