Answer: Y=1
Step-by-step explanation:
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Hope this helps</em></u></h2>
Check the picture below.
![\bf A=\cfrac{h(a+b)}{2}\quad \begin{cases} A=20\\ a=6z-1\\ b=2z+3\\ h=z \end{cases}\implies 20=\cfrac{z[(6z-1)~+~(2z+3)]}{2} \\\\\\ 20=\cfrac{z(8z+2)}{2}\implies 20=\cfrac{2z(4z+1)}{2}\implies 20=z(4z+1) \\\\\\ 20=4z^2+z\implies 0=4z^2+z-20](https://tex.z-dn.net/?f=%5Cbf%20A%3D%5Ccfrac%7Bh%28a%2Bb%29%7D%7B2%7D%5Cquad%20%0A%5Cbegin%7Bcases%7D%0AA%3D20%5C%5C%0Aa%3D6z-1%5C%5C%0Ab%3D2z%2B3%5C%5C%0Ah%3Dz%0A%5Cend%7Bcases%7D%5Cimplies%2020%3D%5Ccfrac%7Bz%5B%286z-1%29~%2B~%282z%2B3%29%5D%7D%7B2%7D%0A%5C%5C%5C%5C%5C%5C%0A20%3D%5Ccfrac%7Bz%288z%2B2%29%7D%7B2%7D%5Cimplies%2020%3D%5Ccfrac%7B2z%284z%2B1%29%7D%7B2%7D%5Cimplies%2020%3Dz%284z%2B1%29%0A%5C%5C%5C%5C%5C%5C%0A20%3D4z%5E2%2Bz%5Cimplies%200%3D4z%5E2%2Bz-20)

since the height is just a length unit, it can't be -2.3646.
Let x, y, z ∈ C, the set of complex numbers.
By definition of ○,
(x ○ y) ○ z = (x + y - 2i) ○ z
… = (x + y - 2i) + z - 2i
… = x + y + z - 4i
and
x ○ (y ○ z) = x ○ (y + z - 2i)
… = x + (y + z - 2i) - 2i
… = x + y + z - 4i
so (x ○ y) ○ z = x ○ (y ○ z), which means ○ is indeed associative under C.
Hi,
Is your question is 5x+2x>=14 then
7x>=14
=>x>=14/7
=>x>=2