Question

Solve each equation 3x^2=80

Answer 1

`x = (4√(15))/(3), x = (-4√(15))/(3)`

or

`x = (\pm4√(15))/(3)`

Explanation:

Hello!

Use the quadratic formula:
`x = (-b \pm √(b^2 - 4ac))/(2a)`

First, let's convert our equation to standard form of a Quadratic: ax² + bx + c = 0

3x² = 80

3x² - 80 = 0

Note, thats the value of b will be 0, as there is no "bx"

Now, solve:

• 
  `x = (-(0) \pm √((0)^2 - 4(3)(-80)))/(2(3))` Plug in values
• 
  `x = (\pm√(960))/(6)` Simplify the radical (Discriminant)
• 
  `x = (\pm8√(15))/(6)` Pull out perfect squares
• 
  `x = (4√(15))/(3), x = (-4√(15))/(3)` Reduce factors

The solutions are
`x = (4√(15))/(3), x = (-4√(15))/(3)`