Two partial receipts for school supply are shown how much does each notebook and each pen cost notebooks and 3 pens tot 195 and 6 notebooks 2 ped and total 162

using elemenation method

hi. how many notebooks were bought from receipt amounting 195 php?

answer:

Surface-area. If a solid is composed of flat surfaces, such as the cube on the right, the surface area is simply the sum of the areas of the flat surfaces (called faces). So, for example, if a each edge of a cube has a length s, the area of one face is s2 since it is a square.