Solution equation: (110-x) + (130-x) = 120 Such as the title

Solution equation: (110-x) + (130-x) = 120 Such as the title

(110-X)+(130-X)=120
240-2x=120
2x=120
x=60

Solve the equation x △ 120 = x △ 130 + 4

x÷120=x÷130+4
x/120-x/130=4
x*(1/120-1/130)=4
x*1/1560=4
x=4*1560=6240

(x-120) (70-x + 130) = 1600

(x-120)(200-x)=1600
-x²+320x-24000=1600
x²-320x+25600=0
(x-160)²=0
x-160=0
x=160

An ellipse is inscribed to a rectangle with length m and width n. find the maximum perimeter of the inscribed rectangle of the ellipse

Ellipse circumference formula: l = 2 π B + 4 (a-b) ellipse circumference theorem: the circumference of an ellipse is equal to the circumference of the circle (2 π b) whose short half axis is the radius plus four times the difference between the length of the long half axis (a) and the length of the short half axis (b)

The second question on page 64 will complete the table! 64 read the first question, think about writing!
Hhang Lan is going to Hainan.It is hot and sunny.She is going shop- ping.What is she going to buy?
Tom is going to Harbin.IT is sold and snowy.HEis going shopping.What
is he going to buy?

Hhang Lan is going to Hainan.It is hot and sunny.She is going shop- ping.What is she going to buy?___ Umbrella, hat or ice cream Tom is going to Harbin.IT is sold and snowy.HEis g...

If the product of polynomial MX ^ 2 + nx-1 and X-2 is a cubic binomial of X, find the value of M, n

(mx^2+nx-1)(x-2)=mx^3+(n-2m)x^2-(2n+1)x+2
Because it is a cubic polynomial, M is not equal to 0, and because it is a binomial and 2 is not equal to 0, so n-2m = 0 and 2n + 1 = 0, the solution is n = - 1 / 2 m = - 1 / 4

The function f (x) = (x-1) sin (π x) - 1, - 1 is known

From F (x) = 0, sin π x = 1 / (x-1),
-1

Is there a fifth grade solution to the equation and a simple score of 25 each

①　8/9 × 15/36 + 1/27
②　3/7× 15/36 + 1/27
③　 8/9× 49/9 - 4/3
④　12× 5/6 – 2/9 ×3
⑤　8× 5/4 + 1/4
⑥　6÷ 3/8 – 3/8 ÷6
⑦　4/7 × 5/9 + 3/7 × 5/9
⑧　6 ×（ 1/2 + 2/3 ）
⑨　5/2 -（ 3/2 + 4/5 ）
⑩　8 × 4/5 + 8 × 11/5
11　7/8 + （ 1/8 + 1/9 ）
12　1 × 5/6 – 5/6
13　9 × 5/6 + 5/6
14　9/7 - （ 2/7 – 10/21 ）
15　3/4 × 8/9 - 1/3
16　9/7 - （ 2/7 – 10/21 ）
17　5/9 × 18 – 14 × 2/7
18　7 × 5/49 + 3/14
19　5/9 × 18 – 14 × 2/7
20　4/5 × 25/16 + 2/3 ×3/4
21　5/7 × 3/25 + 3/7
22　3/14 ×2/3 + 1/6
23　17/32 – 3/4 × 9/24
24　3 × 2/9 + 1/3
25　1/5 × 2/3 + 5/6
26　9/22 + 1/11 ÷ 1/2
27　9/22 + 1/11 ÷ 1/2
28　5/3 × 11/5 + 4/3
29　5/2 -（ 3/2 + 4/5 ）
30　45 × 2/3 + 1/3 × 15
31　7/8 + （ 1/8 + 1/9 ）
32　5/6 + （ 1/2 + 2/3 ）
33　1/4 + 3/4 ÷ 2/3
34　9/7 - （ 2/7 - 10/21 ）
35　8/7 × 21/16 + 1/2
36　3/7 + 49/9 + 4/7
37　101 × 1/5 – 1/5 × 21
38　8/9 + 15/36 + 3/27
39　5/6 + 1/12 + 3/4
40　5/2 - （ 3/2 + 4/5 ）
41　7/8 + （ 1/8 + 1/9 ）
42　9/7 - （ 2/7 - 10/21 ）
43　30/46 - 1/2 + 7/23
44　8/11 + 2/6 + 7/33
45　7/8 + （ 1/8 + 1/9 ）
46　9/7 - （ 2/7 - 10/21 ）
47　30/46 - 1/2 + 7/23
48　8/11 + 2/6 + 7/33
49　1/3 + 3/4 + 1/5
50　3/8 + 8/3 - 1/2
51　1/3 + 3/5 + 1/6
52　3/10 + 10/3 - 1/2
53　6/17 - 1/51 - 1/34
54　8/15 + 7/3 - 8/5
55　（5/8＋4/7）+5/2
56　4/9×（3/7－3/8）
57　5/8－1/2+3/4
58　（5/6＋5/8）-6/7
59　(4/7+2/3)-1/7
60　(1-1/4+8/9)/7/9
61　14 2/3+1/6+3/24+2/21
62　5\2-(3\2+4\5)
63　7\8+1\8+1\9
64　9\7-(2\7-10\21)
65　5\8+5\6+1\9
66　240\400+12\400-150\400
67　186\240+88\240+252\240
68　14\3-(385\42-252\240)
69　2\3+5\9-2\3+5\9
70　6\7+2\15+1\7+13\15
71　8\9+1\4+1\9+3\4
72　1\2+1\3+1\4
73　2\3+5\9-2\3+5\9
equation
1、 (0.5+x)+x=9.8÷2
2、 2(X+X+0.5)=9.8
3、 25000+x=6x
4、 3200=450+5X+X
5、 X-0.8X=6
6、 12x-8x=4.8
7、 7.5*2X=15
8、 1.2x=81.6
9、 x+5.6=9.4
10、 x-0.7x=3.6
11、 91÷x ＝1.3
12、 X+8.3=10.7
13、 15x ＝3
14、 3x－8＝16
15、 7(x-2)=2x+3
16、 3x+9=27
17、 18(x-2)=270
18、 12x=300-4x
19、 7x+5.3=7.4
20、 3x÷5=4.8
21、 30÷x+25=85
22、 1.4×8-2x=6
23、 6x-12.8×3=0.06
24、 410-3x=170
25、 3(x+0.5)=21
26、 0.5x+8=43
27、 6x-3x=18
28、 1.5x+18=3x
29、 5×3-x÷2=8
30、 0.273÷x=0.35
31、 1.8x=0.972
32、 x÷0.756=90
33、 9x-40=5
34、 x÷5+9=21
35、 48-27+5x=31
36、 10.5+x+21=56
37、 x+2x+18=78
38、 (200-x)÷5=30
39、 (x-140)÷70=4
40、 0.1(x+6)=3.3×0.4
41、 4(x-5.6)=1.6
42、 7(6.5+x)=87.5
43、 (27.5-3.5)÷x=4

Given the function f (x) = x * 3-x, then the tangent equation of the curve y = f (x) at the point m (2, f (2))

The answer is y = 11x-16
The process is not complicated
The tangent point is (2,6)
f'(x)=3x^2 -1
So the tangent slope is
f'(2)=3*2^2 -1=11
The tangent equation is
y=11x+b
Tangent through tangent point, B = - 16
So y = 11x-16

It is known that in △ ABC, ab = AC, and its verification: ∠ b > 90 ° (by using the method of disproportion)
It is known that in △ ABC, ab = AC, and the proof is: ∠ B ＜ 90 °
Sorry, wrong number, the condition on the title is wrong!

The title should be "B90"
Because AB = AC
Therefore, B = C
Because ∠ b > 90 degree
So ∠ B + ∠ C > 180 ° is contradictory to the sum of the inner angles of the triangle equal to 180 °
So the hypothesis doesn't hold
So ∠ B