To find the number of solutions of a system of linear equations you need to identify the slope (m) in each equation:

-If the slope is the same in both lines the system has no solution
-If the slope is different in the lines the system has one solution
-If the equation are the same (incluided the value of b) the system has infinitely many solutions
You have the next equations:

Write the equations in slope-intercept form y=mx+b (solve for y).
First equation:

Second equation:

As the equations have the same slope m = -1, the system has no solution (the line doesn't cross each other)
Answer: -2x+3y = 21 which is choice C
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Work Shown:
The slope of the original line is -3/2. The perpendicular slope is 2/3. We flip the fraction and flip the sign. Multiplying the original slope (-3/2) and the perpendicular slope (2/3) will result in -1. Let's use this perpendicular slope and the point to find the equation of the perpendicular line in slope intercept form.
y = m+b
y = (2/3)x+b .... plug in the perpendicular slope
9 = (2/3)(3)+b .... plug in the point (x,y) = (3,9)
9 = 2+b
9-2 = 2+b-2 ... subtract 2 from both sides
b = 7
So y = (2/3)x+b turns into y = (2/3)x+7.
This equation is in slope intercept form.
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Let's convert to standard form
y = (2/3)x+7
3*y = 3*((2/3)x+7) ... multiply both sides by 3 to clear out the fraction
3*y = 3*(2/3)x+3*7 ... distribute
3y = 2x+21
-2x+3y = 21 .... get the x term to the other side (subtract 2x from both sides)
4.998370298991988e+137
Well, thats a large number.
Trust me, im a "prodigy"
Answer:
The number of ways the arrangements can be made of the letters of the word'WONDERFUL' such that the letter R is always next to E is 10,080 ways
Step-by-step explanation:
We need to find the number of ways the arrangements can be made of the letters of the word'WONDERFUL' such that the letter R is always next to E.
There are 9 letters in the word WONDERFUL
There is a condition that letter R is always next to E.
So, We have two letters fixed WONDFUL (ER)
We will apply Permutations to find ways of arrangements.
The 7 letters (WONDFUL) can be arranged in ways : ⁷P₇ = 7! = 5040 ways
The 2 letters (ER) can be arranged in ways: ²P₂ =2! = 2 ways
The number of ways 'WONDERFUL' can be arranged is: (5040*2) = 10,080 ways
So, the number of ways the arrangements can be made of the letters of the word'WONDERFUL' such that the letter R is always next to E is 10,080 ways
There are 10 pairs of sides that touch each other