Question 203479: 1. Solve by substitution or elimination method:
3x – 2y = 26
-7x + 3y = -49
2. Solve by substitution or elimination method:
4x – 5y = 14
-12x + 15y = -42
3. Solve by substitution or elimination method:
-2x + 6y = 19
10x – 30y = -15
Second part of problems:
1. Plot the graph of the equations 2x - 3y = 5 and 4x - 6y = 21 and interpret the result.
2. Plot the graph of the equations 4x - 6y = 12 and x - 5y = 10 and interpret the result.
3. Plot the graph of the equations 8x - 4y = 12 and -4x + 2y = -6 and interpret the result.
You can put this solution on YOUR website! 1. Solve by substitution or elimination method:
3x – 2y = 26
-7x + 3y = -49
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Multiply 1st by 3 ; Multiply thru 2nd by 2:
9x - 6y = 78
-14x + 6y = -98
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Add the two modified equations to solve for "x":
-5x = -20
x = 4
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Substitute into the 1st original equation to solve for "Y":
3*4 - 2y = 26
-2y = 14
y = -7
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2. Solve by substitution or elimination method:
4x – 5y = 14
-12x + 15y = -42
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Multiply thru the 1st equation by 3:
12x -15y = 42
-12x + 15y = -42
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Add the two equations to get:
0 = 0
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This means the two equations are really the same.
The solution is all points of the form (x,(5/4y + (7/2))
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3. Solve by substitution or elimination method:
-2x + 6y = 19
10x – 30y = -15
I'll learve this one to you.
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Second part of problems:
1. Plot the graph of the equations 2x - 3y = 5 and 4x - 6y = 21 and interpret the result.
Put each equation in slope-intercept form:
y = (2/3)x -(5/3)
y = (2/3)x -(7/2)
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Plot two points for each equation.
Draw a line thru each pair of points to get the graphs of the two lines.
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There is no solution for the system because the lines are parallel.
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Cheers,
Stan H.
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2. Plot the graph of the equations 4x - 6y = 12 and x - 5y = 10 and interpret the result.
3. Plot the graph of the equations 8x - 4y = 12 and -4x + 2y = -6 and interpret the result.
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