Это однородное уравнение(10 класс ыы)
делим все на cos^2 x, тогда получается :
2tg^2x+9tgx+9=0
tgx=t
2t^2+9t+9=0
D=81-4*9*2=9
t1==(-9+3)/4=-6/4
t2=(-9-3)/4 = -3
tgx=-6/4 tgx=-3
x=-arctg 6/4+пk x=-arctg3+пk
1) 21/60 (7×3/20×3) и 25/60 (5×5/12×5)
2) 55/120 (11×5/24×5) и 4/120 (1×4/30×4)
3) 9/48 (3×3/16×3) и 28/48 (7×4/12×4)
4) 22/36 (11×2/18×2) и 21/36 (7×3/12×3)
5) 3/36 (1×3/12×3) и 8/36 (2×4/9×4)
6) 16/84 (4×4/21×4) и 39/84 (13×3/39×3)
![1) \: \: задание \: \\ 7 \frac{5}{6} \: и \: - 7 \frac{5}{6} \\ \frac{1}{2} \: и \: - \frac{1}{2} \\](https://tex.z-dn.net/?f=1%29+%5C%3A++%5C%3A++%D0%B7%D0%B0%D0%B4%D0%B0%D0%BD%D0%B8%D0%B5+%5C%3A+%5C%5C+7+%5Cfrac%7B5%7D%7B6%7D+%5C%3A++%D0%B8+%5C%3A++-+7+%5Cfrac%7B5%7D%7B6%7D++%5C%5C++%5Cfrac%7B1%7D%7B2%7D++%5C%3A+%D0%B8+%5C%3A++-++%5Cfrac%7B1%7D%7B2%7D++%5C%5C+)
![2) \: \: задание \: \\ 2.3 > 2.03 \\ 0 > - 5.1 \\ - 7 > - 10 \\ 0.4 > 0 \\ - 1.7 < 1.7](https://tex.z-dn.net/?f=2%29++%5C%3A++%5C%3A+%D0%B7%D0%B0%D0%B4%D0%B0%D0%BD%D0%B8%D0%B5+%5C%3A+%5C%5C+2.3+%3E+2.03+%5C%5C+0+%3E++-+5.1+%5C%5C++-+7+%3E++-+10+%5C%5C+0.4+%3E+0+%5C%5C++-+1.7+%3C+1.7)
![3) \: \: задание \: \\ 4.8 \div ( - 24) = \frac{48}{10} \times ( - \frac{1}{24} ) = - \frac{2}{10} = - 0.2 \\ 5.6 + ( - 3 \frac{1}{2} ) =5 .6 - 3.5 = 2.1](https://tex.z-dn.net/?f=3%29++%5C%3A++%5C%3A+%D0%B7%D0%B0%D0%B4%D0%B0%D0%BD%D0%B8%D0%B5+%5C%3A+%5C%5C+4.8+%5Cdiv+%28+-+24%29+%3D++%5Cfrac%7B48%7D%7B10%7D++%5Ctimes+%28+-++%5Cfrac%7B1%7D%7B24%7D+%29+%3D++-++%5Cfrac%7B2%7D%7B10%7D++%3D++-+0.2+%5C%5C+5.6+%2B+%28+-+3+%5Cfrac%7B1%7D%7B2%7D+%29+%3D5+.6+-+3.5+%3D+2.1)
4) задание
1) Сколько карандашей подарили Маше
![40\% \times 150 = \frac{40 \times 150}{100} = 4 \times 15 = 60 \: \: ( \: карандашей \: подарили \: Маше \: )](https://tex.z-dn.net/?f=40%5C%25+%5Ctimes+150+%3D++%5Cfrac%7B40+%5Ctimes+150%7D%7B100%7D++%3D+4+%5Ctimes+15+%3D+60+%5C%3A++%5C%3A+%28+%5C%3A+%D0%BA%D0%B0%D1%80%D0%B0%D0%BD%D0%B4%D0%B0%D1%88%D0%B5%D0%B9+%5C%3A++%D0%BF%D0%BE%D0%B4%D0%B0%D1%80%D0%B8%D0%BB%D0%B8++%5C%3A+%D0%9C%D0%B0%D1%88%D0%B5+%5C%3A+%29)
2) Сколько осталось карандашей
150 - 60 = 90
3) Сколько карандашей подарили Пете
![\frac{2}{9} \times 90 = \frac{2 \times 90}{9} = 2 \times 10 = 20](https://tex.z-dn.net/?f=+%5Cfrac%7B2%7D%7B9%7D++%5Ctimes+90+%3D++%5Cfrac%7B2+%5Ctimes+90%7D%7B9%7D++%3D+2+%5Ctimes+10+%3D+20)
Ответ: 20 карандашей подарили Пете
![5) \: \: \: задание](https://tex.z-dn.net/?f=5%29+%5C%3A++%5C%3A++%5C%3A++%D0%B7%D0%B0%D0%B4%D0%B0%D0%BD%D0%B8%D0%B5)
а) -2; -1; 0; 1; 2; 3.
б) -5; -4; -3.
1)
-62/58 = (x-500)/522
(x-500)/522 = -62/58
(x-500)/522 = -31/29
x-500 = -31/29*522
x-500 = -31*18
x-500 = -558
x = -558-500
x = -1058
2)
(250+4x)/333 = 59/67
250+4x = 59/67*333
250+4x = 19 314/67
4x = 19314/67-250
4x = 19314/67-16750/67
4x = 2564/67
x = 2564/67*1/4
x = 2564/268 = 641/67 = 9 целых 38/67