MATH GRADE SEVEN ALGEBRA

Question

At the northwest corner of the park, the city is going to install a fountain. The area of the base of the fountain is 9x^(2)-25m^(2). Find the area of the lengths of the sides of the fountain, if x=3 meters.

Answer 1

Area = LW = 9x^2 -25 m^2

plug in x= 3

= 9(3)^2 -25 = 9(9) -25 = 81 - 25 = 56 m^2 = the Area of the base

factor,

9x^2 -25 =(3x-5)(3x+5)

then plug in x=3

= (3x-5)(3x+5) = (3(3)-5)(3(3)+5) = (9-5)(9+5) = 4(14) = 56

sides are 4 m and 14 m

L = 3x+5 = 14 m long

W = 3x-5 = 4m wide