On Saturday my husband (took) me for a meal in a restaurant which (was recommended) in a local newspaper. The restaurant (has been) open for only three months, but it's already quite popular with young people even though it is 30 kilometres away. We enjoyed the evening as the meal was delicious and we (were served) wonderfully. Unfortunately, after we left the restaurant, we had a problem with the car as it wouldn't start though we ( had been trying) to get it started for nearly half an hour. We couldn't understand what (had happened) to the car and decided to leave it behind in the car park untill the following day. We (had) nothing else to do but call a taxi which came in about an hour.
1. 17x-8=20x+7
17x-20x=7+8
-3x=15
x=5
2. х кг- младший,
3х кг-старший,
(х+13) кг -средний.
Всего- 88 кг яблок.
х+3х+х+13=88
5х=88-13
5х=75
х=75:5
х=15(кг)- яблок собрал младший брат.
3. 0,6(х+2)+4,6=0,4(7+х)
0,6x + 1,2+4=2,8+0,4x
0,6x+5,2=2,8+0,4x
0,6x-0,4x=2,8-5,2
0,2x=-2,4
x=-12
4. Пусть х л воды было в каждой цистерне первоначально, тогда
(х-54) л воды стало в первой цистерне, а
(х-6) л воды стало во второй цистерне.
Т.К. в первой стало в 4 раза меньше, чем во второй, то составим уравнение: 4(х-54)=х-6, 4х-216-х+6+0; 3х=210; х=70
ответ: в цистернах было по 70л воды
5. (3x+42)(4.8-0.6x)=0
3x+42=0 4.8-0.6x=0
3x=-42 -0.6x=4.8
x=-14 x=-8