Bỏ dấu ngoặc rồi tính :80+[ {80} - 14]

A.80+80+14 =174

B.80 - 80+ 14 =14

C.80 - 80-14 = -14

D.80 +80  - 14 =146

Bỏ dấu ngoặc rồi tính :80+[ {80} - 14]

A.80+80+14 =174

B.80 - 80+ 14 =14

C.80 - 80-14 = -14

D.80 +80  - 14 =146

mù mắt luôn teo cận hãy rủ lòng thương :<

A(x) = -2x² + 3x - 1

B(x) = 5x² + 3x + 1

a) C(x) = A(x) + B(x)

            = -2x² + 3x - 1 + 5x² + 3x + 1

            = (5x² - 2x²) + (3x + 3x) + (1 - 1)

            = 3x² + 6x

D(x) = A(x) - B(x) 

        = -2x² + 3x - 1 - 5x² - 5x - 1

        = (3x - 5x) - (2x² + 5x²) - (1 + 1)

        = -7x² + 2x - 2

b) A(1) = -2 . 1² + 3 . 1 - 1 = -2 + 3 - 1 = 0

=> x = 1 là nghiệm của đa thức A(x)

B(x) = 5 . 1² + 3 . 1 + 1 = 5 + 3 + 1 = 9

=> x = 1 không là nghiệm của đa thức B(x)

80% của 150 là 120

80% của 120 là 96

vậy 80% của 80% của a = 96

Hello everyone, today I'd like to tell you some information about types and sources of energy. Energy is classified into two main groups: renewable and non-renewable.

The energy generated from natural sources such as the sun, wind, rain, and tides is called renewable energy. They are plentiful and can be generated again and again. They also have low carbon emissions so they are considered green and environment-friendly. Moreover, using renewable energy can reduce your electricity bills. Unfortunately, solar energy can be only used during the daytime but not during night or the rainy season. Geothermal energy also can bring toxic chemicals beneath the earth's surface to the top and can create environmental changes.

Non-renewable energy is the energy taken from other sources that are available on earth.They are limited and will run out in the future. They can't be re-generated in a short time.Fossil fuels - natural gas, oil and coal - are examples of them. They are cheap and easy to use. However, when burnt, they release toxic gases in the air so they cause serious environmental changes such as global warming. And the important thing is that non-renewable sources will expire someday.

My neighbourhood is in the suburbs of Quang Ngai city . I like living here because of many interesting things in my neighbourhood . There are many tall buildings and big houses here. My neighbourhood also has many stores,two markets, a post office, a bank , a stadium so it is very convenient for local people . There are many trees and spaces here so the air here is very fresh . In my neighbourhood there is a big flower field with many kinds of flowers, therefore it is very beautiful in the spring. Morever the people here are friendly and helpful with these reasons . The visitors always come to visit my neighbourhood and they want to stay here longer

My best friend classmate is Nga. The first reason why I like her most is her nice appearance. She has long black hair and beautiful eyes. She is tall and thin enough to participate in VN nexttop model. Not only does she have a pretty appearance but she also has good characteristics. When I feel sad, nervous or stressful, she is always by my side and encourage me to overcome difficult challenges in my life. I'M so grateful for it. Moreover, she once said that:" If oneday you feel like crying, call me..I don't promise that i will make you laugh..but i can cry with you" In addition to that, we have unforgetable experience. In 1997, I was drowning when she appeared and secured me from the Death and since then, we has become closed fiends. We share a lot of things such as dreas, jobs, hobbies,.. I strongly believe that our relationship is lasting forever.

Hello everyone, today I'd like to tell you some information about types and sources of energy. Energy is classified into two main groups: renewable and non-renewable.

The energy generated from natural sources such as the sun, wind, rain, and tides is called renewable energy. They are plentiful and can be generated again and again. They also have low carbon emissions so they are considered green and environment-friendly. Moreover, using renewable energy can reduce your electricity bills. Unfortunately, solar energy can be only used during the daytime but not during night or the rainy season. Geothermal energy also can bring toxic chemicals beneath the earth's surface to the top and can create environmental changes.

Non-renewable energy is the energy taken from other sources that are available on earth.They are limited and will run out in the future. They can't be re-generated in a short time.Fossil fuels - natural gas, oil and coal - are examples of them. They are cheap and easy to use. However, when burnt, they release toxic gases in the air so they cause serious environmental changes such as global warming. And the important thing is that non-renewable sources will expire someday.

My best friend classmate is Nga. The first reason why I like her most is her nice appearance. She has long black hair and beautiful eyes. She is tall and thin enough to participate in VN nexttop model. Not only does she have a pretty appearance but she also has good characteristics. When I feel sad, nervous or stressful, she is always by my side and encourage me to overcome difficult challenges in my life. I'M so grateful for it. Moreover, she once said that:" If oneday you feel like crying, call me..I don't promise that i will make you laugh..but i can cry with you" In addition to that, we have unforgetable experience. In 1997, I was drowning when she appeared and secured me from the Death and since then, we has become closed fiends. We share a lot of things such as dreas, jobs, hobbies,.. I strongly believe that our relationship is lasting forever.

My neighbourhood is in the suburbs of Quang Ngai city . I like living here because of many interesting things in my neighbourhood . There are many tall buildings and big houses here. My neighbourhood also has many stores,two markets, a post office, a bank , a stadium so it is very convenient for local people . There are many trees and spaces here so the air here is very fresh . In my neighbourhood there is a big flower field with many kinds of flowers, therefore it is very beautiful in the spring. Morever the people here are friendly and helpful with these reasons . The visitors always come to visit my neighbourhood and they want to stay here longer

Ta có 35%=10%+10%+10%+5%

Theo đầu bài ta có:

.10% của 80 là.8....

.10% của 80 là...8..

...10% của 80 là...8..

....5.% của 80 là.....4

Vậy 35 % của 80 là:

              8+8+8+4=28

10% của 80 là 8 

20% của 80 là 16

5% của 80 là 4

35%của 80 là 28

Bài này mk vừa làm hôm trước

10% của 80 là 8

10% của 80 là 8

10% của 80 là 8

5% của 80 là 4

35% của 80= 8+8+8+4= 28

\(-\left(515-80+91\right)-\left(2003+80-91\right)\)

\(=-\left(515-80+91\right)-2003-80+91\)

Ta đơn giản còn:

\(=-515-2003\)

\(=-2518\)

Theo cách của mk nghĩ thuj nka!!!^_^

a) - ( 515 - 80 + 91 ) - ( 2003 + 80 - 91 )

=-526-1992=-2518

k nha YoonA