We need to write system of equations for this problem. Reading text we write 1 equation by 1.
first lets name our variables
x - Kiana cards
y - Gary cards
z - Monty cards
m - Willa cards
x = y-3 which we can write as y = x+3
z = x + 7
m = 2z
x + y + z + m = 74
I think easiest way to solve this is to express all variables in last equation and solve for x.
x + x+3 + x + 7+ 2x + 14= 74
5x = 50
x = 10
now we just calculate cards given to each friend
y = 13
z = 17
m = 34
The length is (3/5 -1/5)=2/5
the height is also 2/5
area: length * height =2/5 *2/5=4/5
D is correct.
The complex number -7i into trigonometric form is 7 (cos (90) + sin (90) i) and 3 + 3i in trigonometric form is 4.2426 (cos (45) + sin (45) i)
<h3>What is a complex number?</h3>
It is defined as the number which can be written as x+iy where x is the real number or real part of the complex number and y is the imaginary part of the complex number and i is the iota which is nothing but a square root of -1.
We have a complex number shown in the picture:
-7i(3 + 3i)
= -7i
In trigonometric form:
z = 7 (cos (90) + sin (90) i)
= 3 + 3i
z = 4.2426 (cos (45) + sin (45) i)




=21-21i
After converting into the exponential form:

From part (b) and part (c) both results are the same.
Thus, the complex number -7i into trigonometric form is 7 (cos (90) + sin (90) i) and 3 + 3i in trigonometric form is 4.2426 (cos (45) + sin (45) i)
Learn more about the complex number here:
brainly.com/question/10251853
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