Question

Find the value of x in the equation 2x²+3x+3=20​

Answer 1

Explanation:

we first of all move 20 behind the comma for it to become -20 +3 and we get -17.

then use the product =-34

sum = 3

factors then continue

Answer 2

`x= (-3 - √(145) )/(4) \ \ or\ \ x= (-3 + √(145) )/(4)`

Explanation:

2x² + 3x + 3 = 20​

⇔ 2x² + 3x + 3 - 20 = 0

⇔ 2x² + 3x - 17 = 0

Using the Quadratic Formula to solve a Quadratic Equation :

`x= \frac{-b \pm \sqrt{b^(2)-4ac} }{2a}`

In the equation 2x² + 3x - 17 = 0

a = 2 , b = 3 and c = -17

Then

b² - 4ac = 3² - 4×2×(-17)

= 9 + 8 × 17

= 9 + 136

= 145

Then

b² - 4ac > 0

Then

`x= (-3 \pm √(145) )/(2 * 2)`

Then

`x= (-3 \pm √(145) )/(4)`