Question

Prove that\[\frac{a}{b}+\frac{c}{d}=\frac{ad+cb}{bd}\]

Answer 1

using theorems? or with basic algebra?

Answer 2

Common denominator

Answer 3

just using the basic distributive law, associative laws for addition and multiplication, etc.

Answer 4

let $a := 0
let $b := 1

Answer 5

i wish i had a whiteboard

Answer 6

you can type LaTeX in these boxes and it will render your math

Answer 7

so i have heard.

Answer 8

\begin{array}l\color{#FF0000}{\text{Y}}\color{#FF0000}{\text{ }}\color{#FF7F00}{\text{o}}\color{#FF7F00}{\text{ }}\color{#FFE600}{\text{u}}\color{#FFE600}{\text{ }}\color{#00FF00}{\text{ }}\color{#00FF00}{\text{ }}\color{#00FF00}{\text{c}}\color{#00FF00}{\text{ }}\color{#0000FF}{\text{a}}\color{#0000FF}{\text{ }}\color{#6600FF}{\text{n}}\color{#6600FF}{\text{ }}\color{#8B00FF}{\text{ }}\color{#8B00FF}{\text{ }}\color{#FF0000}{\text{a}}\color{#FF0000}{\text{ }}\color{#FF7F00}{\text{l}}\color{#FF7F00}{\text{ }}\color{#FFE600}{\text{s}}\color{#FFE600}{\text{ }}\color{#00FF00}{\text{o}}\color{#00FF00}{\text{ }}\color{#0000FF}{\text{ }}\color{#0000FF}{\text{ }}\color{#0000FF}{\text{d}}\color{#0000FF}{\text{ }}\color{#6600FF}{\text{o}}\color{#6600FF}{\text{ }}\color{#8B00FF}{\text{ }}\color{#8B00FF}{\text{ }}\color{#FF0000}{\text{t}}\color{#FF0000}{\text{ }}\color{#FF7F00}{\text{h}}\color{#FF7F00}{\text{ }}\color{#FFE600}{\text{i}}\color{#FFE600}{\text{ }}\color{#00FF00}{\text{s}}\color{#00FF00}{\text{ }}\color{#0000FF}{\text{.}}\color{#0000FF}{\text{ }}\end{array}