Hey forum, help me with this obvious quadratics question that's busting my head anyway? (1 Viewer)

[BrokenHourglass]

http://imgur.com/QszlOKW

This question right here.
I know the answer is D.
The marking guidelines didn't say anything else.
I have no idea where the 33 and 4 came from, nor do I know how to get the x on the other side.
I feel confident in maths until I get to the point where all four of the multiple choice options confuse me and I feel like selling everything I own and joining the army.

 

[Drdusk]

http://imgur.com/QszlOKW

This question right here.
I know the answer is D.
The marking guidelines didn't say anything else.
I have no idea where the 33 and 4 came from, nor do I know how to get the x on the other side.
I feel confident in maths until I get to the point where all four of the multiple choice options confuse me and I feel like selling everything I own and joining the army.

It's just the quadratic formula



where b=-5, a=2, c=-1

 

[CM_Tutor]

In a MCQ like this, you can test each answer with a calculator as a way to find which is true.

For example, (A) has

​

Now, try on of these in the given equation,

​

So, (A) can't be the solution.

Using the quadratic formula to actually find the solution is preferable, but this method (or even finding the value without a calculator) is an option as a fall-back approach for an MCQ.

 

[Constantspy977]

http://imgur.com/QszlOKW

This question right here.
I know the answer is D.
The marking guidelines didn't say anything else.
I have no idea where the 33 and 4 came from, nor do I know how to get the x on the other side.
I feel confident in maths until I get to the point where all four of the multiple choice options confuse me and I feel like selling everything I own and joining the army.

bruh I go pre uni, and I had the exact same question on our term test