А) 5ab-3ac = a(5b - 3c)
Б)2a/2b+12ab/2 =a(1/b + 6b)
В)8a/3+4a/2
= 4a(2/3 +1/2) = 4 2/3a
0,04=4/100=1/25
log(5)1/25=-2
Х^2 + V x + N = 0
1) - 13
( - 13 )^2 - 13V + N = 0
N - 13V + 169 = 0
2) 4
4^2 + 4V + N = 0
N + 4V + 16 = 0
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N = - 4V - 16
- 4V - 16 - 13V + 169 = 0
- 17V = - 153
V = 9
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N = - 4 • 9 - 16 = - 36 - 16 = - 52
9 > - 52
Ответ 9 ; - 52
4(х+2)+5х=71
4х+8+5х=71
9х=63
Х=7 скорость лодки