I taught 9th grade algebra for a couple of years, and the students always wonder why algebra is important to know. Mano Singham, a physicist with a science weblog out of Case Western University, posted a great example of how it might be useful. The video he posted is below, and I will be describing just one of the reasons why she has no business talking about science.
In the video, a homeopath describes how homeopathy works. She manages to mangle whole branches of physics, but someone having survived 9th grade algebra should be able to tell that she speaks nonsense. She claims that there is almost no mass in the universe (I think she is trying to say that atoms are mostly empty space), and ties this to Einstein’s famous “E=mc2” equation. Since there is “almost no mass in the universe,” the “m” on the right side of the equation essentially disappears. Since it disappears, she claims that Einstein’s equation is essentially “E=c^2,” and goes on to say something about how our eyes are really important.
Even if it were true that there is almost no mass in the universe (it isn’t), the variable “m” would not “disappear” in the sense that we simply erase it; she would have to mean that it “goes to zero.” In this case, the equation would be “E=0,” not “E=c^2.” She wanted “m” to be approximately “0,” but she essentially said that it is approximately “1.” Anyone surviving high school algebra should know that 0x=0. This should be a red flag to any educated person.
From now on, whenever anyone asks you why they need to learn math, you can answer: “so you do not get suckered by homeopaths.”