SOLUTION: (4t-5)^2-10(4t-5)+21=0

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Question 946597: (4t-5)^2-10(4t-5)+21=0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use a substitution,
u=4t-5
.
.
.
u%5E2-10u%2B21=0
%28u-7%29%28u-3%29=0
Two solutions:
u-7=0
u=7
4t-5=7
4t=12
t=3
and
u-3=0
u=3
4t-5=3
4t=8
t=2