Solving equations and inequalities through substitution example 2

less than 1m read

·Nov 11, 2024

Mario started the day with five fire flowers. He used some, and now only has three left. If u is the number of flowers he's used, we can write the following equation: how many fire flowers did Mario use?

So, he started with five, he uses some of them, so we subtract the number he used and he ends up with three. There are a bunch of ways that you could do it. One way is you literally could probably do this in your head.

"Hey, I took away some number from five, and I got three!" You probably know, "Hey, well, if I take two away from five, I'm going to get three." So, he used two flowers.

The other way that you could think about doing it is, "Well hey, we got only four options here. Let me substitute each of them in here." Maybe I was able to do this one in my head, but if I had something more complicated, let me try out these choices.

So if he only took a zero away, it'd be five minus zero; he'd still, of course, be left with five. If he took one away, then of course he'd only have four left. If he took three away, he'd have two left. But if you took two away, five minus two is indeed three.

The third way you'll learn this as we go into more of how algebra works, and also the why, is that you could systematically solve it, but we'll go into that in future videos.

So, he used two fire flowers.

Long run supply when industry costs are increasing or decreasing | Microeconomics | Khan Academy

Genetic Engineering and Diseases – Gene Drive & Malaria

View All

Gradient and contour maps

So here I want to talk about the gradient in the context of a contour map. Let’s say we have a multivariable function, a two-variable function, f of x, y, and this one is just going to equal x * y. So we can visualize this with a contour map just on the …

Alaska Gives, Alaska Takes (Clips) | Alaska: The Next Generation

Woo, good shot, Sonta! Going down. That was distance right there. Thanks. Was that your last shot you hit it on? Second. Second, huh? Yeah. That was out there. That was a good reach. I felt like that was going to happen. I wasn’t quite sure and then. Oh,…

Caribou Blanket | Life Below Zero

Mr. Caribou hides gonna make a nice blanket. You don’t just rip a caribou hide off of the caribou and start sleeping on it. It’s got to be cleaned up. There’s still fat on here. There, these warm flies lay eggs on caribou and their fur. In summertime, the…

Solar and lunar eclipses

In a previous video, we asked ourselves a very important question. As the moon has its 28-day cycle around the Earth, we talked about how a new moon is when the moon is between the Earth and the Sun. From the Earth’s point of view, or from the point of vi…

Worked example: Using Le Chȃtelier’s principle to predict shifts in equilibrium | Khan Academy

Carbon monoxide will react with hydrogen gas to produce methanol. Let’s say that the reaction is at equilibrium, and our job is to figure out which direction the equilibrium will shift: to the left, to the right, or not at all. As we try to make changes t…

Worked example: Analyzing the purity of a mixture | AP Chemistry | Khan Academy

We’re told you have a solid that you know is mostly sodium chloride. You suspect that it might have, or it may have, some sodium iodide, potassium chloride, or lithium chloride as well. When you analyze a sample, you see that it contains 73% chlorine by m…

Solving equations and inequalities through substitution example 2

More Articles