Fig. 14.36 3 A concrete floor is 4 m long and 3 m wide. Calculate: a the area of the floor, b the cost of making the floor if concrete is N2 400 per m². What is the area, in m², of the floor of a hall that is 6 metres square? (6 metres square means 6 m by 6 m.) ​

Step-by-step explanation:

Area of floor = length * width

                     = 4 * 3

                     = 12 sq.m

Cost of making the floor = 12 * 2400

                                         = N 28800

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places

step-by-step explanation:

the triangles are similar. therefore the corresponding sides are in proportion:

              cross multiply

            divide both sides by 32