A solid box with height 10cm, width 50cm and length 30cm needs to be painted. The paint costs £0.14 per cm2.
How much will it cost to paint the box?

£644

Step-by-step explanation:

Since you are painting on the outside, you will need to find the surface area:

2(10 x 50) + 2(10 x 30) + 2(30 x 50)

= 4600 cm^2

multiply it by the cost:

4600 x 0.14 = £644

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below: