The 3rd equation is a linear combination of the 1st and 2nd, hence, we can disregard it: . Substracting the 1st equation from the 2nd one, in order to eliminate at least one square, we get
Ang ika-3 equation ay isang guhit kumbinasyon ng 1st at 2nd, kaya, maaari naming ipagwalang-bahala ito: . Subtracting ang ika-1 equation na mula sa 2nd isa, upang puksain ang hindi bababa sa isang parisukat, makuha namin ang