Linear Equations

Welcome to Linear Equations! Your one-stop-shop for basic Linear Algebra. Linear equations make life very easy! You can See into.predict the future outcomes of certain problems.

The most common Rule or function.linear equation is y = mx + b.

To actually use this equation, you have to know what the variables represent, and what they mean. So let's break it down.

M is the Constant rate of change.slope which is known as m = Δ y ÷ Δ x = vertical change/horizontal change = rise/run In the case of our table, the x value increases by 1, while the y value by 5, so we divide the change in y by the change in x. In the example of our table, this is 3 ÷ 1 = 3.

B is the Starting value or flat fee.y-intercept. B can be found by looking for the y value when the x value is 0, either by backtracking on your table or seeing the corresponding number to the x value equaling 0. That's the y-intercept (in the table below, it's 5).

Firstly, plug in the formula. For example: if I want to find what the y value will be, when the x value is 279, I plug in 279 for x: y = 3(279) + 5. Once solved, you should get an answer of 842.
But, what if you want to find the x value when the y value is 842? Well that's actually quite simple, you can find the x value by plugging in 842 for y: 842 = 3x + 5. Now all you have to do is inverse operations, and once solved you should get an answer of 279!

↻ Flip Table
x 0 1 2 3 4 5
y 5 8 11 14 17 20