Square of X / x + 3 = 9 / x + 3 & nbsp; & nbsp; & nbsp; x=2y 2x+5y=9

Square of X / x + 3 = 9 / x + 3 & nbsp; & nbsp; & nbsp; x=2y 2x+5y=9

x²/（x+3)=9/(x+3)
Multiply both sides by X + 3
x²=9
X = 3, x = - 3 (the denominator is 0, rounding off)
So x = 3
2.x=2y
2x+5y=9
Substituting x = 2Y into 2x + 5Y = 9
So 9y = 9
y=1
x=2
So x = 2, y = 1

Equations {MX + 2Y = 5
3x-3y=n
）
Please solve the above equations

{ mx+2y=5 {3mx+6y=15 ①
3x-3y=n ﹋ 6x-6y=2n ② ﹋
①+② { 3mx+6x=2n+15 ﹋
x=(2n+15)/(3m+6)
Take x into 2 to get y = (2n + 15) / (3m + 6)

The equation,
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A. 10m/sB. 8m/sC. 6m/sD. 12m/s

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Fourth grade oral arithmetic questions (with answers)
The more the better, the most selected as the "best answer"!

1.45+15×6= 135 2.250÷5×8=400 3.6×5÷2×4=60 4.30×3+8=98 5.400÷4+20×5= 200 6.10+12÷3+20=34 7.(80÷20+80)÷4=21 8.70+(100-10×5)=120 9.360÷40= 9 10.40×20= 800 11.80-25= 55 12.70+45=115 13.90×...

The weight of the car and passengers of an elevator is 1.2t, which rises from one floor to seven floors in 10s. If the height of each floor is 3M, at least what is the power of the elevator motor?

It is known that g = 1.2 * 10 ^ 4N, t = 10s, H = (7-1) * 3 = 18m
Find p
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A: the power is 2.16 * 10 ^ 4W

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