You have a lot of questions here, try breaking them up into multiple posts and you may get more responses.
I will help with some.
<span>(x+3)=0
The solution is just -3.
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3m(m-4)=0
The two solutions are 0 and 4.
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(r-3)(r+2)=0
The two solutions are and 3 and -2.
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I hope this gets you started in the right direction.
32% means 32/100
32/100 = 16/50 = 8/25, which is the lowest you can get because you can no longer divide it to get a whole number.
A; 8/25.
-4 x 9= -36 and the when you add 5 to -36 you get -31. Hope this helps
<h2>f = -5</h2><h3></h3><h3>f(x) = 4x - 9</h3><h3>Add 9 to both sides</h3><h3>f(x) + 9 = 4x</h3><h3>Divide x from both sides</h3><h3>f + 9 = 4</h3><h3>Subtract 9 from both sides</h3><h3>f = -5</h3><h3></h3><h3><em>Please let me know if I am wrong.</em></h3>