1) 9-6=3.
Ответ: 3 маленьких мяча купили для класса.
<span> y=(5/(x+6))-</span>√<span>(</span><span>4-7x)
{4-7х</span>≥0 { -7x≥-4 { x≤4/7
x≠-6 , x≠-6, x≠0
------------------- -6--------------------------- 4/7----------------------->x
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Ответ:(-∞;-6)∪(-6;4/7]
36-14-12=10..............................................