= 7 2/5 - 1 4/5
= 37/5 - 9/5
= 28/5
In short, Your Answer would be: 28/5 or 5 3/5
Hope this helps!
Answer:
x ∈ {-5, -1}
Step-by-step explanation:
Here's the solution using the quadratic formula:
![x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}=\dfrac{-24\pm\sqrt{24^2-4\cdot 4\cdot 20}}{2\cdot 4}\\\\=\dfrac{-24\pm\sqrt{576-320}}{8}=\dfrac{-24\pm\sqrt{256}}{8}\\\\=\dfrac{-24\pm 16}{8}=-3\pm 2=\{-5,-1\}](https://tex.z-dn.net/?f=x%3D%5Cdfrac%7B-b%5Cpm%5Csqrt%7Bb%5E2-4ac%7D%7D%7B2a%7D%3D%5Cdfrac%7B-24%5Cpm%5Csqrt%7B24%5E2-4%5Ccdot%204%5Ccdot%2020%7D%7D%7B2%5Ccdot%204%7D%5C%5C%5C%5C%3D%5Cdfrac%7B-24%5Cpm%5Csqrt%7B576-320%7D%7D%7B8%7D%3D%5Cdfrac%7B-24%5Cpm%5Csqrt%7B256%7D%7D%7B8%7D%5C%5C%5C%5C%3D%5Cdfrac%7B-24%5Cpm%2016%7D%7B8%7D%3D-3%5Cpm%202%3D%5C%7B-5%2C-1%5C%7D)
The real zeros are -5 and -1.
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There are many ways to check your answer. One of them is to look at the given quadratic, which has no changes of sign in its coefficients. (They are all positive.) That means there can be no positive real roots, so already you know that x=0.5 won't work.
Also, the constant in the quadratic is the product of the roots, For your roots, their product is -7/4, so even multiplying by 4 (the leading coefficient in the given quadratic), you don't get anything like 20.
9514 1404 393
Answer:
yes
Step-by-step explanation:
You can go at this a couple of ways:
1. The total length David needs is (1.75 m) × 4 = 7.00 m. His 7.28 m piece is long enough to provide the pieces he needs.
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2. The length of each piece when the wood is cut into quarters is ...
(7.28 m)/4 = 1.82 m
This is longer than the 1.75 m needed, so each piece is long enough.