Solve for x: 3 over 4 x + 5 over 8 = 4x?

5 Answers

• (3/4 x + 5) / (8) = 4x

  Cross multiply:

  8 (4x) = (3/4 x + 5)

  32x = 3/4 x + 5

  32x – 3/4x = 5

  128/4 x – 3/4x = 5

  125/4 x = 5

  125x = 20

  x = 20/125

  x = 4/25

  Hope this helps. 🙂

• assuming expression is

  3/4x + 5/8 = 4x

  is the same as

  3/4x + 5/8 = (4x)/1

  NOTE that our LOWEST common denominator is 8x, so multiply each fraction top and bottom until you get the denominators to have 8x.

  2(3)/2(4x) + x(5)/x(8) = 8x(4x)/1(8x)

  2(3)/8x + x(5)/8x = 8x(4x)/8x

  now drop denominators and solve using numerators

  2(3) + x(5) = 8x(4x)

  6 + 5x = 32x^2

  32x^2 – 5x – 6 = 0

  a = 32, b = -5, c = -6…..

  x = (-b +/- √(b^2-4ac)) / 2a

  x = (-(-5 +/- √((-5)^2 -4(32)(-6))) / 2(32)

  x = (5 +/- √(25 -(-768))) / 64

  x = (5 +/- √793) / 64

  can’t simplify further

• I’m assuming that you have this:

  (3/4x)+(5/8)=4x

  And that is what I will solve.

  Multiply everything by 8:

  6X+5=32X

  Move the 6X to the other side. When it’s on the left, its sign is + when it moves, its sign becomes –

  +5=32X-6X

  Solve:

  5=26X

  X=5/25

• 3/4x + 5/8 = 4x

  – 3 1/4x = – 5/8

  (4/13)13/4x = (4/13)5/8

  x = 5/26.

• is the answer really 4/25