#### • Class 11 Physics Demo

Explore Related Concepts

#### • linear equation real life

Question:I need a real life example of a quadratic equation (ax2+bx+c=0) Also two examples for x would be great, thanks.

Question:I am needing to have a real life quadratic equation example for school and I don't even know where to start!!! I keep finding examples that are way too complex and I don't quite understand it yet..... I need some help!

Answers:One way of approaching this is to work backwards. Find a simple quadratic, and then think of words that might represent a real-life situation. Often, these real-life situations involve circumstances where you have two unknown numbers, but you know two things about them: 1. Their sum or difference 2. Their product. To find a simple quadratic, note that, if you take two expressions involving x and multiply them, the result will be a quadratic. Go with something simple, say: (x - 2)(x + 3) = 0 x^2 + x - 6 = 0 x^2 + x = 6 Then, refactor the left-hand side to get: x(x + 1) = 6 So, now we have two numbers (x and x + 1). We know their difference is 1, and their product is 6. Pick two things to be represented by x and x + 1, respectively. Say x represents pairs of shoes, and x + 1 represents belts. Then, x(x + 1) is the number of possible different combinations that can be made from x pairs of shoes and x + 1 belts. We already know this number is 6. So, our "real-life problem" might be something like this: Sally is flying to London to conduct a six-day seminar on human rights. Due to space limitations, she must pack one fewer pairs of shoes than belts. How many shoes and belts must Sally pack, if she doesn't want to wear the same shoe-belt combination twice? Now, working forwards, we would set up the problem like this: Let x = the number of pairs of shoes Sally packs. Then, x + 1 = the number of belts Sally packs. The number of shoe-belt combinations is: x(x + 1) = 6 x^2 + x - 6 = 0 (x - 2)(x + 3) = 0 x = {-3, 2} Since Sally can't have -3 pairs of shoes, the solution is 2 pairs of shoes, which means 2 + 1 = 3 belts. OK, this isn't exactly "real life" stuff (why would anybody ever be required to pack exactly one fewer pairs of shoes than belts?) but it gives a good idea of how these word problems are put together: Work backwards from the solution, and find words to symbolize what the solution actually means.

Question:I have a project where I have to write a 5 page essay about quadratic equations. I have heard about people using them for missiles in the army, and satellite dishes. If you have any information, please, PLEASE, help me.

Answers:Yes, missiles and other projectiles under the influence of gravity (or some other accelerating agent), will follow a parabolic trajectory (if we ignore air resistance and some other factors). For example, at time t, the vertical height of an object launched into the air will be: x(t) = (1/2)*g*t^2 + v0*t + x0 where t represents the time since the object was launched, g represents the acceleration due to gravity, v0 represents the objects initial vertical velocity, and x0 represents the objects initial vertical height. For more information, try searching for "projectile motion," "free-fall motion," "trajectory," etc.

Question:I need to show the representation of X and Y when I do this function???

Answers:Any kind of projectile motion, like throwing a ball or shooting a cannon/gun because if you use time as your variable, the equation represents acceleration, velocity, and distance.