Solve for x: 3 over 4 x + 5 over 8 = 4x
x = __________________ Write your answer as a fraction in simplest form. Use the “/” symbol for the fraction bar.
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^24ac)) / 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=32X6X
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