SOLUTION: Can you please help me solve by using the subtitution and elimination method (unless there is no infnite number or solution.)
y = 4 - x,
3x + 4y = 21
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y = 4 - x,
3x + 4y = 21
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Question 62783: Can you please help me solve by using the subtitution and elimination method (unless there is no infnite number or solution.)
y = 4 - x,
3x + 4y = 21 Answer by jai_kos(139) (Show Source):
You can put this solution on YOUR website!
Given
y = 4 - x --->(1)
3x + 4y = 21 --->(2)
Now substitue equation(1) in (2), we get
3x+ 4(4-x) = 21
3x + 16 -4x= 21
16 -x = 21
Get all the numbers on one side, we get
16 -21 = x
-5 = x
Now substitue for x =-5 in equation(1), we get
y = 4 -(-5) = 4 + 5 = 9
Hence the value of x = -5 and y = 9
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