Question

Solve this equation with steps:

8x³-125=0
You must use differences of squares to get the answer.

Answer 1

Answer

2.0

Explanation:

x2+8x+15=0

x2+8x=-15

x2-8x+(8x1/2)2=-15+(8x92)

(X-8/2)2=-15+64/4

(x-8/2)2=4/4

take the square root of both sides

X-8/2=v4/4

X-8/2+2/2

x=8/2+2/2 or 8/2-2/2

x=10/2 or 6/2

x=5 or 3 an

Answer 2

• x = 2.5

Explanation:

The given is the equation of degree 3 so no differences of squares applicable

The solution is:

• 8x³ - 125 = 0
• 8x³ = 125
• (2x)³ = 5³
• ∛(2x)³ = ∛5³
• 2x = 5
• x = 5/2 = 2.5

It has one real root only