Answer:
Explainations to part A is written below.
Part B : x = 25 is the solution as length cannot be negative.
Step-by-step explanation:
Hey there, it's pretty simple!
The formula for the volume of a cube is
Volume = Length × Width × Height.
Let's assume length = x, height = 2x - 30, and width as 10
also note that volume is 5000, plugging this into the equation, we get
(x)(10)(2x - 30) = 5000
10x (2x-30) = 5000
x(2x-30) = 500
(this is how they got 500 and hence the -500 when we shift this to another side to create a quadratic equation).
2x^2 - 30x = 500
2x^2 - 30x - 500 = 0
Part b)
Factoring 2(x^2 - 15x - 250) = 0, we get
2 (−25) (+10)
tadah!
