SOLUTION: Solve |7x-4| = 10

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Question 168899: Solve |7x-4| = 10
Answer by Electrified_Levi(103) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, Hope I can help,
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Solve +abs%287x-4%29+=+10+
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Absolute value will always make the numbers inside positive, absolute value is the distance away from "0" on the number line
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|5| = 5, it is 5 units away from zero
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|-5| = 5, it is also 5 units away from zero
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+abs%287x-4%29+=+10+, to get rid of the absolute value signs, we can say the left side equals 10, as well as (-10), since the absolute will make it positive, so we really have two equations
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+7x-4+=+10+, and +7x-4+=+%28-10%29+, now let us solve for "x"
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First equation, +7x-4+=+10+
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We need to move (-4) to the right side
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+7x-4+=+10+ = +7x-4+%2B+4+=+10+%2B+4+ = +7x+=+14+, to find "x" we need to divide each side by "7"
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+7x+=+14+ = +7x%2F7+=+14%2F7+ = +x+=+2+, we can check by replacing "x" with "2" in the equation
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+7x-4+=+10+ = +7%282%29-4+=+10+ = +14-4+=+10+ = +10+=+10+ (True)
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Now let us solve the second equation, +7x-4+=+%28-10%29+
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We need to move (-4) to the right side
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+7x-4+=+%28-10%29+ = +7x-4%2B4+=+%28-10%29+%2B+4+ = +7x+=+%28-6%29+, to find "x" we will divide each side by "7"
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+7x+=+%28-6%29+ = +7x%2F7+=+%28-6%29%2F7+ = +x+=+-6%2F7+, we can check by replacing "x" with (-6%2F7)
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+7x-4+=+%28-10%29+ = +7%28-6%2F7%29-4+=+%28-10%29+ = +%28-6%29-4+=+%28-10%29+ = +%28-10%29+=+%28-10%29+ (True)
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Your two answers are ( +x+=+2+ ), and ( +x+=+-6%2F7+ )
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If we replaced these two numbers into the original equation, they should work
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replace with "2", abs%287x-4%29+=+10 = abs%287%282%29-4%29+=+10+ = abs%2814-4%29+=+10 = abs%2810%29+=+10 = +10+=+10+ ( absolute value means that it is "10" units from "0" )
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replace with ( -6%2F7 ), abs%287x-4%29++=+10 = abs%287%28-6%2F7%29-4%29+=+10 = abs%28%28-6%29-4%29+=+10+ = abs%28-10%29+=+10 = +10+=+10+ ( True ) ( Remember, the absolute signs will make any number positive, absolute value is just how far the number is from "0", (-10) is 10 units from "0"
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Your two answers are
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+x+=+2+
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+x+=+-6%2F7+
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Hope I helped, Levi