What are the exact solutions of x2 − 5x − 7 = 0?

Question

anonymous · Answer

attachment

anonymous · Answer

@jim_thompson5910 , help please ?

jim_thompson5910 · Answer

are you familiar with the quadratic formula?

ghazi · Answer

use $$D= (-b \pm \sqrt{b^2-4ac})/2a$$

jim_thompson5910 · Answer

If not, then you can use this to solve other (similar problems). So I recommend writing this into your notes

In this case, 

a = 1

b = -5

c = -7


Plug them into the formula below and simplify

$$\Large x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}$$

$$\Large x = \frac{-(-5)\pm\sqrt{(-5)^2-4(1)(-7)}}{2(1)}$$

$$\Large x = \frac{5\pm\sqrt{25-(-28)}}{2}$$

$$\Large x = \frac{5\pm\sqrt{53}}{2}$$

jim_thompson5910 · Answer

Does that help? Or are you stuck somewhere?

anonymous · Answer

It helps, thankssssss ! Life saver

jim_thompson5910 · Answer

alright, I'm glad I could help out

anonymous · Answer

Thanks

jim_thompson5910 · Answer

you're welcome