Solving equation 8x + 6 (15-x)

Solving equation 8x + 6 (15-x)

This is not an equation. The equation is an equation with equal sign and unknowns. This is not an equation because it has no equal sign

Solving equation x-3 / 8x = 400

5/8x=400
The solution is: x = 640

3 times 27 times 3 ^ 9 = 3 ^ x + 8 to find the value of X

3 times 27 times 3 ^ 9 = 3 ^ x + 8
Namely
3×3³×3^9
=3^(1+3+9)
=3^13
=3^(x+8)
x+8=13
x=5

How to calculate the voltage and current for 12V battery charging

The voltage and current should be designed according to the characteristics of the battery, rather than calculated. For lead-acid batteries, a floating charge voltage of 13 ~ 13.5V can be simply applied to them for a long time

Simple calculation of 13-8-7-8

13-8 / 9 7-1 / 8
=13/9-（7/8+1/8)
=13/9-1
=4/9

When the voltage at both ends of the motor is u, the current is I, and the resistance of the motor coil is r, the maximum mechanical power output of the motor is 0
When the voltage at both ends of the motor is u, the current is I, and the resistance of the motor coil is r, the maximum mechanical power output of the motor is ()
A．UI B．I²R C．UI-I²R D．UI+I²R
Speed, 20 rewards in one day

C．UI-I²R

2.74 * 9.9 + 0.274 how can it be easily calculated?
To write complete! Urgent!

2.74*9.9+0.274
=2.74*9.9+2.74*0.1
=2.74*（9.9+0.1）
=2.74*10
=27.4

There is an ammeter with a measuring range of 200 μ A and an internal resistance of 0.8 ohm. Now the measuring range is expanded to 1 mA. How large should the parallel resistance be?
Find out the concrete process and formula

After the range is expanded, the current through the micro ammeter is 200 microampere, and the current through the parallel resistance is 800 microampere. The voltage at both ends is equal, the internal resistance of the micro ammeter is U / 200, the parallel resistance is U / 800, and the resistance value of the parallel resistance should be 1 / 4 of the internal resistance of the micro ammeter

It is known that the cubic root sign a with x = 3 and y = negative is a set of solutions of the equation 3x + 2Y = 4
Find the sum of the cube root of - A and the square root of A

3x + 2Y = 4 means that the cubic root a is 4, so a is 64, so the cube root of - A is - 4, and the square root of a is 8. And 4

Physics problems of electric energy
The dial of electronic energy meter is marked with 3000imp / kW · H
The electric appliance is connected to the meter separately for 20 min, and the indicator light of the electric energy meter flashes 300 times. The electric energy consumed by the electric appliance in the above time is () J
Please give me the process. I calculated 1800j

It's just energy, not time
Every kilowatt hour flashes 3000 times, 300 times is 0.1 kilowatt hour, equivalent to 360000j
You have miscalculated