Hey there! I'm happy to help you!
We want to find what d equals, or basically, we want to find <u>d=?</u>
How do we find this?
Well, as you saw, we want to find d equaling something. To do this, we need isolate d on one side of the equation to see what it equals on the other side.
How do we do this, though?
To solve equations, we will use <u>inverse operations</u>. If we had the equation 1+x=2, we have to get the x alone! We have to get rid of the one. To do this, we will subtract 1 from both sides. Why?
Well, if you have a +1 and then you subtract 1, it will equal 0. So we will basically have 0+x=2-1, or x=1!
In our case, we see that d is being divided by -9. To get rid of it, we will multiply both sides of the equation by -9 (division and multiplication are inverse operations!) so that it stays balanced and so we can find our d.
d/-9=-6
d/-9×9=-6/-9 We divide both sides by -9
d=54
You can also plug this value back into the original equation and it will make sense!
54/-9=-6
I hope that this helps you! Have a wonderful day!
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