Find the value of X in triangles **by subtracting known angle measurements from 180 degrees**. Since the value of all angles within a triangle must equal 180 degrees, if you know at least two angles, you can subtract them from 180 to find the missing third angle.

## How do you find X formula?

Isolate “x” on one side of the algebraic equation by subtracting the sum that appears on the same side of the equation as the “x.” For example, in the equation “x + 5 = 12”, rewrite the equation as “x = 12 – 5” and solve for “x.” The solution is “x = 7.”

## What is the value X?

more The letter “x” is often used in algebra to mean a value that is not yet known. It is called a “variable” or sometimes an “unknown”. In x + 2 = 7, x is a variable, but we can work out its value if we try! A variable doesn’t have to be “x”, it could be “y”, “w” or any letter, name or symbol.