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I'm having trouble with this. i know it's simple, but I'm honestly blanking out on how to do this:
2 equations:
X = 12L - 0.75L^2
A = 24L - 2.25L^2
What does L equal when X and A intersect?
I know this means when X = A, which is 12L - 0.75L^2 = 24L - 2.25L^2
The answer is X = A at 8 but how do I find this?
Do you know how to solve quadratic equations? As skeeter showed, with A= X, you have . Adding to both sides and subtracting 24L from both sides, you get . The simplest way to solve a quadratic equation is to factor (if you can). Here, we can see there is an "L" in both parts so we can factor that out: . The crucial arithmetic point here is that if ab= 0, then either a= 0, or b= 0, or both. If the first factor, L, is 0, then, of course, we get the solution L= 0. If the other factor, 1.5L- 12= 0, we have 1.5L= 12 and then L= 12/1.5. 1.5 is, of course, the same as 3/2 and dividing by 3/2 is the same as multiplying by 2/3: = 12(2/3)= 24/3= 8.