A+bi is the form of a complex number. a is on the x axis, bi is on the y axis:
3-4i ( x positive, y negative) Q4
-1-3i (both x, y negative) Q3
4+i ( both x, y positive) Q1
-2+2i (x neg, y pos) Q3
The slope is 5/2. You can find the slope by using y2-y1/x2-x1. 7-2/6-4= 5/2.
The heat produced by current I is
H = I²R
where
R = resistance.
According to the formula, heat produced is proportional to the square of the current.
When a current of I = 2 amps is applied, the heat produced is
H = 10x³ + 80.
This heat includes heat due to a fixed current of 2 amps, and heat due to a variable current of x amps.
Because the heat produced is proportional to the square of the current, write the expressions as
H = (10x)*(x²) + 20*(2²)
The second term on the right is heat due to the fixed current of 2 amps, written as
20*(2²).
Therefore the fixed resistance is R = 20 ohms, and the square of the fixed current is 2².
The first term represents heat due to variable resistance, written as
(10x)*(x²).
Therefore the variable resistance is 10x, and the square of the variable current is x².
Answer:
The variable current is 10x.
Answer i pick is A. got to MULTIPLE BY 2 FOR X
