The substitution method is a technique for solving a system of equations. This article reviews the technique with multiple examples and some practice problems for you to try on your own.

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When solving a system of equations using substitution, you can isolate one variable and substitute it with an expression from another equation. This will allow you to solve for one …

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So this one is faster. It's simpler. And over time, you might even start being able to do this in your head. This top one, you still didn't mess up by just setting u equal to sine of 5x, we just have to …

Learn to solve the system of equations -3x - 4y = -2 and y = 2x - 5 using substitution.

It doesn't necessarily matter whether this will be useful in real life, the main point of doing any type of complicated math is to train your brain to use different ways of thinking to come to solutions.

Well there's two ways you could do it. I could just take the negative seven and replace it, the H with that negative seven, or I could actually try to simplify this expression first and then do the …