Answer:
59
Step-by-step explanation:
Let c and b represent the scores of Colin and Brian respectively. Then
c + b = 59. Since brian scored 59 more points than Colin, that means c = 0 and b = 59. Their combined score is 0 + 59 = 59.
x+30=2x-70, x-70=30, x=100
180=(2(100)-70)+5y, 180=130+5y, 50=5y, y=10
Answer:
85
Step-by-step explanation:
https://www.calculatorsoup.com/calculators/statistics/mean-median-mode.php
First join the log4 on the left:
log4( x*(x-3) = log4(-7x+21)
Then x = -7, works: -7*(-10)=70 = -7*(-7)+21
x=-3, 18 = 42, does not work
x=3 0=0 works,
However, when one puts x = -7 in the *original* exression, log4(-7) or log4(-10) do not exist (you know why?). So x= -7 is extraneous.
Now x=3 gives log4(0) on the left and right, which does not exist.
So, C is the answer, both are extraneous. Seem to work but indeed don't work in the *original* equation