The following problem: $$h(x)=7x^2 - 5x -2$$
Factors into this: $$7(x-1)(x+2/7)$$

The problem can be solved using the quadratic formula: $$ax^2 +bx +c = 0$$
$$x=(-b+-\sqrt{b^2-4ac)/})2a$$

However, can the problem also be solved using the following formula?

$$x2+px+q=0$$
$$x=-p/2 +- \sqrt{(p/2)^2 - q}$$

Question

The following problem: $$h(x)=7x^2 - 5x -2$$
Factors into this: $$7(x-1)(x+2/7)$$

The problem can be solved using the quadratic formula: $$ax^2 +bx +c = 0$$
$$x=(-b+-\sqrt{b^2-4ac)/})2a$$

However, can the problem also be solved using the following formula?

$$x2+px+q=0$$
$$x=-p/2 +- \sqrt{(p/2)^2 - q}$$

mathslover · Answer

$$\large{h(x) = 7x^2-5x-2}$$  
$$\large{h(x) = 7x^2+7x-2x-2}$$
$$\large{h(x) = 7x(x+1)-2(x+1)}$$
$$\large{h(x) = (7x-2)(2x+1)}$$

jiteshmeghwal9 · Answer

$$7x^2-7x+2x-2$$$$7x(x-1)+2(x-1)$$$$(7x+2)(x-1)$$

anonymous · Answer

I can solve the problem, but what I need is to udnerstand the formula x2+px+q=0. So far I haven't been able to solve the problem using this particular formula. :/

jiteshmeghwal9 · Answer

take common$$7(x-1)(x+2/7)$$

anonymous · Answer

Still not using the formula though. I need to solve it using: 

$$x2+px+q=0$$
$$x=-p/2 +- \sqrt{(p/2)^2 - q}$$

mathslover · Answer

@math0101 it is NOT given to us that : 

h(x) = 0 

hence we can't use that formula