Algebraic fractions: x-1 / 3 = x+1 / 4

x-1 / 3 = x+1 / 4

I can't remember how to simplify this type of algebraic fractions... I think the way to do it was quite simple but I forgot. Can anyone help me please?

Thanks in advance.

(I don't know if the numerators should be in brackets...?)

Reply 1

Pheylan

You can cross multiply:

4(x-1) = 3(x+1)
4x - 4 = 3x + 3
x = 7

Reply 2

besomebody

multiply the numerators by the opposite denominator.

4(x-1)=3(x+1)

Reply 3

SK-mar

yeh what they've said

Reply 4

james.h

NJade

x-1 / 3 = x+1 / 4

I can't remember how to simplify these type of algebraic fractions... I think the way to do it was quite simple but I forgot. Can anyone help me please?

Thanks in advance.

(I don't know if the numerators should be in brackets...?)

\displaystyle \frac{(x-1)}{3}=\frac{(x+1)}{4}[br]\implies 4(x-1)=3(x+1)

Just multiply by the denominator on each side of the expression to get rid of the fractions. Then you can expand the brackets and solve as usual. :smile: