Kyūjitai form of 負数

solve (a problem); answer (a question); unravel (a riddle) / comb; untangle (hair)

untie; unravel; undo (a fastening); unwrap / dispel (doubts); clear up (a matter)

to use / to employ / to make use of, to apply / to spend

needed, necessary

need, necessity

mathematics (field of study)

question, problem on homework etc. / a question; a matter (of time etc.) / a problem (something that needs to be dealt with); a trouble / an issue; a matter

to lose / to defeat / to carry

(mathematics) negativity, being negative (less than zero) / (physics) negativity, being negative (of electrical charge of an electron) / negativity, being negative (bad, pessimistic)