How many gallons of paint are needed to paint the walls of a rectangular prism shaped room that is 20 feet by 13 feet and 8 feet high if 1 gallon of paint covers 40 square feet?

  13.2 gallons

Step-by-step explanation:

The wall area is the product of the room's perimeter length and the wall height:

  A = Ph = (2(L+W))h = 2(20 +13)(8) = 528 . . . . square feet

The number of gallons required to cover this area is then ...

  (528 ft^2)/(40 ft^2/gal) = 13.2 gal

13.2 gallons of paint are required to paint the walls of the room.

the system of inequity is

step-by-step explanation:

from the given graph it is noticed that we have two related lines. one is solid and another is dashed.

if a line passing through two points, then the equation of line is

the solid line passing through the points (0,4) and (4,0).

the related equation of solid line is .

similarly, find the related equation of dashed line. the dashed liune passing through the points (0,0) and (3,1).

the related equation of dashed line is

from the given graph it is noticed that the point (0,1) lies on the shaded region, therefore the point (0,1) must be satisfied by the related equations.

check the related equations by the point (0,1).

this statement is true if the sign of inequality is < instead of equality. since it is an solid line therefore the sign of inequality will be . the required inequality is

similarly, check the second related equation.

it is a dashed line, so this statement is true if the sign of inequality is > . the required inequality is

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl