Question

I Don't Understand Quadratic Equation Equations:
Solve 3x^2 + 5x + 7 = 0. Round Solutions To The Nearest Hundredth

Answer 1

3x² - 5x - 7 = 0
3x² - 5x = 7
x² - 5/3x = 7/3
x² - 5/6x = 84/36 + 25/36
(x - 5/6)² = 109/36
x - 5/6 = 1.740051

1st factor:
= x - 0.833333 + 1.740051
= x + 0.906718

2nd factor:
= (3x² - 5x - 7)/(x + 0.906718)
= 3x - 7.720154

Values of x:
x + 0.906718 = 0, x = - 0.906718
3x - 7.720154 = 0, 3x = 7.720154, x = 2.573385

Answer: x = - 0.906718, 2.573385

Proof:
3(- 0.906718)² - 5(- 0.906718) = 7
3(0.822138) + 4.53359 = 7
2.46641 + 4.53359 = 7
7 = 7

Proof:
3(2.573385)² - 5(2.573385) = 7
3(6.62231) - 12.8669 = 7
19.8669 - 12.8669 = 7
7 = 7

Answer 2

You can also just use the quadratic equation formula. Just set in 3 to A 5 to B and 7 to C