Posted in English 9

Grammar in context exercises

Solution A – recycle paper, metal and glass
a If everyone recycles paper, companies won’t cut down so many trees.
b If everyone recycles metal and glass, we won’t waste valuable resources.
c If everyone recycles paper, metal, and glass, we won’t produce so much rubbish.

Solution B – turn off lights, don’t drive so much, insulate your house
d If everyone turns off unwanted lights, they will save a lot of electricity.
e If everyone walks or cycles, they won’t waste so much oil and petrol.
f If everyone insulates their houses, they won’t waste so much energy for heating.

Solution C – use renewable energy
g If countries use more wind and water power, they won’t depend so much on power stations.
h If countries use power stations less, they will cause less air pollution.

a. If you don’t train hard, you won’t succeed in sport.
You won’t succeed in sport unless you train hard.

b. If you train regularly, you can improve your performance.

You can improve your performance as long as you train regularly.

c. If you enjoy your sport, it doesn’t really matter whether you succeed or not.
It doesn’t really matter whether you succeed or not as long as you enjoy your sport.

d. If you don’t eat and sleep properly, you won’t develop as an athlete.
➡ You won’t develop as an athlete unless you eat and sleep properly.

e. Take a spare pair of running shoes in case you need them.

f. Take a waterproof coat with you in case it rains.

g. Take a warm jumper in case you get cold when you stop.

h. Take a first-aid kit in case someone gets injured.

Posted in Հանրահաշիվ 9

Հանրահաշիվ 9

265.

Ա) ×+y=3

1+2=3 Ճիշտ է

Բ) 2×+y=1

2(1)+2= 2+2=4≠1 սխալ է

Գ) 3×+2y=7

3(1)+2(2)=3+4=7 Ճիշտ է

Դ) x² + y² = 3

1¹+2²=1+4=5≠3 սխալ է

Ե)

x² + y² = 5

1²+2²=1+4=5 Ճիշտ է

Զ) ху- х = 1

(1)(2)-1=2-1=1 Ճիշտ է

266.

Ա) Ճիշտ է

Բ) Սխալ է

Գ) Ճիշտ է

Դ) Սխալ է

Ե) Ճիշտ է

Զ) Ճիշտ է

267.

ա) 3x+2y+z=4 Ճիշտ է

բ) x — y + z=1 Ճիշտ է

գ) x+2y+3z=2 Սխալ է

դ) xy+2xz+yz=2 Ճիշտ է

ե) x2+y2+z2=5 Ճիշտ է

զ) x2+2y2-z2 Սխալ է

268.

ա) x+y+z=10 (2;3;5)

բ) x2+y2+x2 (4;2±√)5)

գ) xy+yx+yz=3 (1;1;1)

դ) xy-yx+yz= 1 (0;1;1

269.

270.

271.

272.