Maths Olympiad Prep

Library / /52 of 241

, 2021

Algebra Difficulty 1.4 Junior Find the answer Canada

If x=2x=2 and y=x25y=x^2-5 and z=y25z=y^2-5, then zz equals

Pick one

Solution

Since x=2x=2 and y=x25y = x^2 - 5, then y=225=45=1y = 2^2 - 5 = 4 - 5 = -1.

Since y=1y=-1 and z=y25z = y^2 - 5, then z=(1)25=15=4z = (-1)^2 - 5 = 1 - 5 = -4.

Want a route through all this instead of an archive? The track puts 2,444 problems in a working order, from Junior Challenge level to the IMO shortlist.

Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.