Question

Solve the following quadratic equation and give your answer correct to 2 decimal places.

x

2

– 3 (x + 3) = 0​

Answer 1

Answer:

$x = (3 + \sqrt{45} ) \div 2 \\ or \\ x = (3 - \sqrt{45}) \div 2$

Step-by-step explanation:

${x}^{2} - 3(x + 3) = 0 \\ {x}^{2} - 3x - 9 = 0$

So,

$x = ( - ( - 3 )+ \sqrt{ { (- 3)}^{2} - 4 \times 1 \times ( - 9) } ) \div 2 \: \: \\ or \: \\ x = ( - ( - 3 )- \sqrt{ { ( - 3)}^{2} - 4 \times 1 \times ( - 9)} \div 2$

$x = (3 + \sqrt{45} )\div 2 \: \: \\ or \\ x = (3 - \sqrt{45} ) \div 2$