(460000/(1 + r)^13·(1 + r)^6 + 40449)·(1 + 0.05)^7 = 460000
q = 1 + r
(460000/q^13·q^6 + 40449)·(1 + 0.05)^7 = 460000
460000/q^13·q^6 + 40449 = 460000/(1 + 0.05)^7
460000/q^13·q^6 = 460000/(1 + 0.05)^7 - 40449
460000/q^7 = 460000/(1 + 0.05)^7 - 40449
q^7 = 460000/(460000/(1 + 0.05)^7 - 40449)
q = (460000/(460000/(1 + 0.05)^7 - 40449))^{1/7}
q = 1.070000250
r = q - 1 = 0.070000250