What's the algebraic expression of "4 times a number cubed decreased by 7"?

Statement:  "4 times a number cubed decreased by 7"

Let a number be  x is denoted as an arbitrary variable.

Now, cubed means raise x to the third power  i.e

then, 4 times a number cubed i.e

Decreased by 7 means, subtract 7  

⇒

Therefore, the algebraic expression for the given statement is,

answer: f true

step-by-step explanation:

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15