6. s=gt^2/2
s=560. g=10. 2s=gt^2. t^2=2s/g. t=корень из 2s/2 = корень из 112= 23.7с Ответ: t=23.7 с высоты 560 м.
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1 1/4 - (1/15 + 1/10 + х) = 3/4
5/4 - (2/30 + 3/30 + х) = 3/4
- (5/30 + х) = 3/4 - 5/4
- (5/30 + х) = - 2/4
5/30 + х = 2/4
1/6 + х = 1/2
х = 1/2 - 1/6
х = 3/6 - 1/6
х = 2/6
х = 1/3
<u>проверка:</u>
1 1/4 - (1/15 + 1/10 + 1/3) = 3/4
5/4 - (2/30 + 3/30 + 10/30) = 3/4
5/4 - 15/30 = 3/4
5/4 - 1/2 = 3/4
5/4 - 2/4 = 3/4
3/4 = 3/4
{x^2+y^2=9 {x^2+y^2=9 {x^2+(3-x)^2=9
{x+y=3 {y=3-x {y=3-x
{x²+9-6x+x²=9 {2x²-6x=0 {x(x-3)=0
{y=3-x {y=3-x {y=3-x
{x=0
{y=3
{x=3
{y=0
ответ (0;3) (3;0)