I am trying to start again with math, giving it a second shot after i completly gave up on math for about 10y. I looked up multiple cheet sheets and rules, but they all say different things. My problem especially +29 – +59. The rule thing i got from the internet says + – + = larger integer’s sign, but then another tutorial said well if you reverse + and -, then you can get the answer that way, but they are 2 different answers. And i’m confused too about what, like what’s the point of doing the operations if we can just change whatever symbols we want, but then we do but nothing matches as the result so i’m just confused.
I just don’t get it, none of the rules match and in my head none of it even makes any sense. So i feel like i need to memorize the rules, but there are no rules. Pls help, i started crying due to the fustration because now i remembered why i despised math so much.
Update: I started being able to complete operations, even of 5 in a row. Thank you all! Ended up dropping tje unecessary + and just – – = + idk, but i’m doing it.
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I would think about it like this:
You’re standing on a very long, straight race track. You’re standing on a solid line that we’ll call the starting line. Ahead of you, way past the horizon, is a brilliant sunset.
When you have positive (+) numbers, what you should do is face toward the sunset, and take that many steps toward it. So if you had, say, “29” (which you seem to be writing as “+29”, kinda odd but not wrong, if it helps you keep track then go for it), then what you’d do is face toward the sun, and take 29 steps toward it.
When you have negative numbers, what you should do is face *away* from the sunset, and take the given number of steps in that direction. (Or, you can think of it like walking backwards, you’ll get to the same place either way.) So if you had “-59”, you turn away from the sunset and take 59 steps.
Addition would be like doing this for several numbers in sequence. So if you had “29 + 59”, you’d face toward the sunset, take 29 steps, then immediately take 59 more steps. If you then asked yourself, “how many steps away am I from that starting line?” you’d have your answer. 29 + 59 would be 88 steps in total. If you turned around and walked 88 steps, you’d get back to the starting line.
Subtraction is weird. It’s kind of a roundabout way to say, “add, but do the opposite of the thing after this”. So, “+59 – +29”, for example, is actually the same as “+59 + -29”. You can convert the subtraction to addition and flip the sign of whatever came after it. After you do this, we’re left with only addition. That’s something we already know how to handle. We can now do the same procedure: walk 59 steps toward the sunset, then turn around and walk 29 steps away from the sunset. How many steps are we away from the starting line? 59 – 29 = 30 steps away.
So, now the thing you asked about. Subtraction but when the second number is “bigger”. Say, for something like “+29 – +59”. We can do what we did last time, and convert that subtraction into addition: “+29 + -59”. Now, we walk. Face to the sunset, walk 29 steps. Then, turn around, and walk 59 steps. How far away from the starting line are we now? Well, if you walk 29 steps away, then turn around, and walk 59 steps, you’ll actually come back to the starting line on your 29th return step. But you still have 30 steps to go, right? You keep walking those 30 extra steps. But this time you’re behind the line instead of in front of it. So, in a sense, you’re still “30 steps away” from the starting line, but the fact that you’re *behind* the line this time is special. That’s actually what it means to get a negative answer: you returned to the 0 mark and went past it in the direction opposite the way you usually go. Or, looking at it another way, it would take that many steps in your normal direction just to get back to the 0 mark. So 29 – 59 = -30. If you faced toward the sunset again, walked 30 steps, you’d get back to the starting line.
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