✅ SOLVING a SYSTEM of EQUATIONS just by thinking🤔 a little

Suppose we want to solve this system of 4 equations and 4 unknowns. To do this, we could use any of a variety of standard methods: Gauss, Cramer, and so. But another option is to just think and arrive at a quicker solution.

[@luiscasanova3241]

Sometimes the mechanical is bad no, worse.

[@discovermaths]

Thanks Luis!!!

[@joseantoniobarreranunez9949]

Good work: stop and think a little before going through. Thank you.

[@discovermaths]

Thanks José Antonio!!

[@mahmoudalbahar1641]

Many thanks for your great videos. And I suggest making video about non-integer base of numeration.

[@babayaguita]

Thank you so much for this video!

[@discovermaths]

Thanks Ev ;)

[@orenkrimchansky]

wow!thanks

[@discovermaths]

Thank you!!!

[@devondevon4366]

x=1 y=2 u=-1 and z=-1 5x+ 5y + 5u + 5z=5 hence x+ y+ u + z =1 x+y =1- u-z 1-u-z + z+ 2u =0 (substitute in equation 4) hence 1+u=0 hence u=-1 hence x+ y + 2z= 1 and x+ y+z = 2 substitute u=-1 into equation 3 and 4 z=- 1 subtracting the above two equations hence 2x+ y = 4 and or 4x+ 2y=8 multiply by 2 x+ 2y=5 substituting -1 and -1 into equation 1 and 2 4x+ 2y=8 -3x=-3 x =1 hence y=2 answer =1 y =2 u=-1 and z=-1