(Originais Teachy 2023) - Question Very Hard of Mathematics

In a renovation, an architect decides to completely cover a right prism with a square base with ceramic tiles that are in the shape of squares. The prism is 3 meters high and the edge of the base measures 2 meters. The tiles are 20 cm on each side. The architect will need to calculate the amount of tiles to cover the entire surface of the prism. How many tiles will be needed to completely cover the prism?

In a large engineering system, a building is being designed and energy efficiency is a major concern. To ensure the efficiency of heating and cooling, the air conditioning system must be sized according to the specific needs of the building. The engineer in charge of the project must solve a system of linear equations to determine the ideal operating temperatures. Let the following be the system of equations that models the thermal behavior of the building: 2x + y + 3z = 10, 4x - 6y + 8z = 5, 3x + 7y + 5z = 18. The engineer must rewrite this system of equations in the matrix form Ax = b, where A is the matrix of coefficients, x is the vector of unknowns, and b is the vector of constant terms.

João is building a fence for his garden. He decided to make the fence in the shape of a rectangle and already knows that the height is 4 meters and the base is 7 meters. Help João calculate the perimeter of the fence. What is the perimeter of João's garden fence?