Hi please help, in the below picture, how do i solve this into a single number?

Question

jack1 · Answer

attachment

jack1 · Answer

a4 = 1
a3 = 14
a2 = 65
a1 = 112
... im so lost   :-/

parthkohli · Answer

Are these determinants?

jack1 · Answer

yess...?

jack1 · Answer

i remember seing this once when i was doing matrixes or vectors, and you .... multiply diagonally or something...? or subtract top from bottom?

parthkohli · Answer

$$\dfrac{-(a_4a_1 - a_2a_3)}{a_3}$$

jack1 · Answer

ur a legend, cheers @ParthKohli !

parthkohli · Answer

So the $a_3$ would cancel out in one term, and in the other one you note that $14 \times 8 = 112$.

No problem.  :)

shadowlegendx · Answer

Parth you could've just beaten those numbers down into one piece. Ya know...smashing them together with those fist of yours c;

parthkohli · Answer

Wat.