Odgovor:
# x = -1 / 25 barva (bela) ("xxx") alibarva (bela) ("xxx") x = 3 #
Pojasnilo:
Če # 5x = sqrt (74x + 3) #
potem
(po kvadriranju obeh strani)
#barva (bela) ("XXX") 25x ^ 2 = 74x + 3 #
(odštevanje # 74x + 3 # z obeh strani)
#barva (bela) ("XXX") 25x ^ 2-74x-3 = 0 #
(faktoring)
#barva (bela) ("XXX") (25x + 1) (x-3) = 0 #
(dve možnosti)
#barva (bela) ("XXX") {: (25x + 1 = 0, barva (bela) ("xx") ali barva (bela) ("xx"), x-3 = 0), (rarr x = - 1/25,, rarrx = 3):} #
Odgovor:
#x = -1/25, 3 #
Pojasnilo:
# 5x = sqrt (74x + 3) #
# (5x) ^ 2 = 74x + 3 #
# 25x ^ 2 = 74x + 3 #
# 25x ^ 2 - 74x - 3 = 0 #
#x = (-b + - sqrt (b ^ 2 - 4ac)) / (2a) #
#x = (74 + - sqrt (-74 ^ 2 + 300)) / 50 #
#x = (74 + - 76) / 50 #
#x = -1/25, 3 #
