Giải giúp mik vs ạ mik cần gấp
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1 are
2 am
3 is
4 are
5 are
6 are
7 is
8 is
9 is
10 are
IV
1 is writing
2 are losing
3 is having
4 is staying
5 am not lying
6 is always using
7 are having
8 Are you playing
9 are not touching
10 Is - listening
11 Is- winning
12 am not staying
13 is not working
14 is not reading
15 isn't raining
16 am not listening
17 Are they making
18 Are you doing
19 Is - sitting
20 is - doing
21 are-putting
22 are-wearing
23 is-studying
2, am
3, is
4,are
5,are
6,are
7,is
8,is
9,is
10,are
IV
1,2,7 OK
3,is having
4,has stayed
5,am not lying
6,always uses
8,Are-playing
9,not to touch
10,Is-listening
11,Are-winning
12,am not staying
13,isn't working
14,isn't reading
15,isn't raining
16,am not listening
17,Are-making
18,Are-doing
19,Is-sitting
20,is-doing
21,do-putting
22,do-wear
23,is-studying
1/ Xét \(\Delta ABC\) và \(\Delta HAC\) có:
∠A = ∠AHC = 90 độ
∠C là góc chung
Do đó: △ABC ∼ △HAC (g . g)
2/ Ta có: \(\Delta HAC\sim\Delta ABC\)
\(\Rightarrow\dfrac{AC}{HC}=\dfrac{BC}{AC}\)
\(\Rightarrow AC.AC=HC.BC\)
\(\Rightarrow AC^2=HC.BC\) (đpcm)
3/ Đặt BD là x, theo tính chất đường phân giác, ta có:
\(\dfrac{AB}{AC}=\dfrac{BD}{DC}\Rightarrow\dfrac{9}{12}=\dfrac{x}{15-x}\)
\(\Rightarrow9\left(15-x\right)=12x\)
\(\Rightarrow135-9x=12x\)
\(\Rightarrow135=12x+9x\)
\(\Rightarrow135=21x\)
\(\Rightarrow x\approx6,4\)
Độ dài của DC là: \(15-x\Rightarrow15-6,4=8,6\)
Vậy BD = 6,4 cm và DC = 8,6 cm
1. a) 6² : 4 . 3 + 2 . 5²
= 36 : 4 . 3 + 2 . 25
= 9 . 3 + 50
= 27 + 50
= 77
b) 5 . 4² - 32 : 4²
= 5 . 16 - 32 : 16
= 80 - 2
= 78
c) 80 - (4 . 5² - 3 .2³)
= 80 - (4 . 25 - 3 . 8)
= 80 - (100 - 24)
= 80 - 76
= 4
d) 2448 : [119 - (23 - 6)]
= 2448 : (119 - 17)
= 2448 : 102
= 24
e) 23 . 85 + 15 . 23 + 170
= 23 . (85 + 15) + 170
= 23 . 100 + 170
= 2300 + 170
= 2470
f) 3³ . 2 - 5 . 2023⁰ + 36 : 3²
= 27 . 2 - 5 . 1 + 36 : 9
= 54 - 5 + 4
= 53
2. a) 123 - 5.(x + 4) = 38
5.(x + 4) = 123 - 38
5.(x + 4) = 85
x + 4 = 85 : 5
x + 4 = 17
x = 17 - 4
x = 13
b) (3.x - 2⁴) . 7³ = 2 . 7⁴
3x - 16 = 2 . 7⁴ : 7³
3x - 16 = 2 . 7
3x = 14 + 16
3x = 30
x = 30 : 3
x = 10
c) (2600 + 6400) - 3.x = 1200
9000 - 3x = 1200
3x = 9000 - 1200
3x = 7800
x = 7800 : 3
x = 2600
d) [(6.x - 72) : 2 - 84] . 28 = 5628
(6x - 72) : 2 - 84 = 5628 : 28
(6x - 72) : 2 - 84 = 201
(6x - 72) : 2 = 201 + 84
(6x - 72) : 2 = 285
6x - 72 = 285 . 2
6x - 72 = 570
6x = 570 + 72
6x = 642
x = 642 : 6
x = 107
e) 70 - 5(x - 3) = 45
5(x - 3) = 70 - 45
5(x - 3) = 25
x - 3 = 25 : 5
x - 3 = 5
x = 5 + 3
x = 8
f) 10 + 2.x = 4⁷ : 4⁵
10 + 2x = 4²
10 + 2x = 16
2x = 16 - 10
2x = 6
x = 6 : 2
x = 3
g) 2.x - 138 = 2³.2²
2x - 138 = 2⁵
2x - 138 = 32
2x = 32 + 138
2x = 170
x = 170 : 2
x = 85
h) 231 - (x - 6) = 1339 : 13
231 - (x - 6) = 103
x - 6 = 231 - 103
x - 6 = 128
x = 128 + 6
x = 134
Câu 3:
a: Ta có: \(2x\left(3x-1\right)-\left(x-3\right)\left(6x+2\right)\)
\(=6x^2-2x-6x^2-2x+18x+6\)
=14x+6
b: Ta có: \(2x\left(x+7\right)-3x\left(x+1\right)\)
\(=2x^2+14x-3x^2-3x\)
\(=-x^2+11x\)
Câu 2:
a: Ta có: \(\left(-8x^5+12x^3-16x^2\right):4x^2\)
\(=-8x^5:4x^2+12x^3:4x^2-16x^2:4x^2\)
\(=-2x^3+3x-4\)
b: Ta có: \(\left(12x^3y^3-18x^2y+9xy^2\right):6xy\)
\(=12x^3y^3:6xy-18x^2y:6xy+9xy^2:6xy\)
\(=2x^2y^2-3x+\dfrac{3}{2}y\)
c: Ta có: \(\dfrac{x^3-11x^2+27x-9}{x-3}\)
\(=\dfrac{x^3-3x^2-8x^2+24x+3x-9}{x-3}\)
\(=x^2-8x+3\)
d: Ta có: \(\dfrac{6x^4-13x^3+7x^2-x-5}{3x+1}\)
\(=\dfrac{6x^4+2x^3-15x^3-5x^2+12x^2+4x-5x-\dfrac{5}{3}-\dfrac{10}{3}}{3x+1}\)
\(=2x^3-5x^2+4x-\dfrac{5}{3}-\dfrac{\dfrac{10}{3}}{3x+1}\)
\(D=10\cdot\left(-2.5\right)\cdot0.4\cdot\left(-0.1\right)\)
\(=10\cdot1\cdot2.5\cdot0.4\)
=10
My grandma often works in the garden in her free time.
What are you doing with the stove?
3. My grandma often works in the garden in her free time.
4. What are you doing with the stove?