Объясните пожалуйста, как решаются такие неравенства...

Вот к примеру, 

Является ли данное число а решением данного неравенства:

7-3x меньше 13, a=-15, a=4.

начертите отрезок ТР, длина которого равна 7см 8мм. Отметьте на нем точку Е так, чтобы  ТЕ = 2см 6мм. Какова длина отрезка ЕР?

Сократите пож текст кратко,на завтра надо:

In Ancient Greece the typical unit of political and social organization was the polis. The Archaic period was followed by the Classical period, during which the Greeks made radical experiments with political, artistic and philosophical ideas, all of which have had a lasting influence on Western civilization. One  of the most fascinating things that the greeks have left us is their legends. We remember them us they have  become part of our culture too. This expression goes back to the story of Achilles, one of the greatest heroes of Greek legends.The legend says that when he was born, the fates, the goddesses that controlled man's life and future, told his mother that he would die young.  So Achilles' mother, Thetis, wanted to protect her baby and dipped him in the water of the River Styx. This was supposed to protect him from deadly wounds. Every part of Achilles' body was thus made safe against in jury, except one part- the heel by which his mother held him. Later, during the Trojan War Achilles, a handsome young man, become famous as the greatest og the Greek warrios but was killed by a poisonous arrow that entered his heel, the one part of his body that had not been dipped in the Styx.

Определи количество звуков и букв в словах: семья, семя, съел, сел, яма, прямо, полью, прополю, тетя, шьет.