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Solve for u. u+1/4=-4/5

1 Answer

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Answer:

u = (-21)/20

Explanation:

Solve for u:

u + 1/4 = (-4)/5

Put each term in u + 1/4 over the common denominator 4: u + 1/4 = (4 u)/4 + 1/4:

(4 u)/4 + 1/4 = -4/5

(4 u)/4 + 1/4 = (4 u + 1)/4:

1/4 (4 u + 1) = -4/5

Multiply both sides of (4 u + 1)/4 = (-4)/5 by 4:

(4 (4 u + 1))/4 = (-4)/5×4

4×(-4)/5 = (4 (-4))/5:

(4 (4 u + 1))/4 = (-4×4)/5

(4 (4 u + 1))/4 = 4/4×(4 u + 1) = 4 u + 1:

4 u + 1 = (-4×4)/5

4 (-4) = -16:

4 u + 1 = (-16)/5

Subtract 1 from both sides:

4 u + (1 - 1) = (-16)/5 - 1

1 - 1 = 0:

4 u = (-16)/5 - 1

Put (-16)/5 - 1 over the common denominator 5. (-16)/5 - 1 = (-16)/5 - 5/5:

4 u = (-16)/5 - 5/5

-16/5 - 5/5 = (-16 - 5)/5:

4 u = (-16 - 5)/5

-16 - 5 = -21:

4 u = (-21)/5

Divide both sides by 4:

u = ((-21)/4)/5

5×4 = 20:

Answer: u = (-21)/20

User Eduardo Lino
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