Answer:
Area of the shaded region = 6.88 cm²
Step-by-step explanation:
Area of the shaded region = Area of the rectangle - Area of the semicircle
Area of the rectangle = Length × Width
Length of the rectangle = AD = 8 cm
Width of the rectangle = OP = 4 cm [OP, OB and OC are the radii of the circle which are equal in measures]
Area of the rectangle = 8 × 4 = 32 cm²
Area of the semicircle = 
= 
= 
= 25.12 cm²
Area of the shaded region = 32 - 25.12
= 6.88 cm²
The function is:
B ( t ) = 4 * e^(0.8 t)
4 * e^(0.8 t) = 400
e^(0.8 t) = 400: 4
e^(0.8 t) = 100 / ln
ln e^(0.8 t) = ln 100 ( and since: ln e = 1 and ln e^x = x * ln e )
0.8 t = 4.6
t = 4.6 : 0.8 = 5.76 ≈ 6
Answer:
D ) 6 hours.
Answer:
thanks for the points ily
so we have the points of (0,-7),(7,-14),(-3,-19), let's plug those in the y = ax² + bx + c form, since we have three points, we'll plug each one once, thus a system of three variables, and then we'll solve it by substitution.
well, from the 1st equation, we know what "c" is already, so let's just plug that in the 2nd equation and solve for "b".
well, now let's plug that "b" into our 3rd equation and solve for "a".
![\bf -19=9a-3b-7\implies -12=9a-3b\implies -12=9a-3(-1-7a) \\\\\\ -12=9a+3+21a\implies -15=9a+21a\implies -15=30a \\\\\\ -\cfrac{15}{30}=a\implies \blacktriangleright -\cfrac{1}{2}=a \blacktriangleleft \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{and since we know that}}{-1-7a=b}\implies -1-7\left( -\cfrac{1}{2} \right)=b\implies -1+\cfrac{7}{2}=b\implies \blacktriangleright \cfrac{5}{2}=b \blacktriangleleft \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ ~\hfill y=-\cfrac{1}{2}x^2+\cfrac{5}{2}x-7~\hfill](https://tex.z-dn.net/?f=%5Cbf%20-19%3D9a-3b-7%5Cimplies%20-12%3D9a-3b%5Cimplies%20-12%3D9a-3%28-1-7a%29%20%5C%5C%5C%5C%5C%5C%20-12%3D9a%2B3%2B21a%5Cimplies%20-15%3D9a%2B21a%5Cimplies%20-15%3D30a%20%5C%5C%5C%5C%5C%5C%20-%5Ccfrac%7B15%7D%7B30%7D%3Da%5Cimplies%20%5Cblacktriangleright%20-%5Ccfrac%7B1%7D%7B2%7D%3Da%20%5Cblacktriangleleft%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Band%20since%20we%20know%20that%7D%7D%7B-1-7a%3Db%7D%5Cimplies%20-1-7%5Cleft%28%20-%5Ccfrac%7B1%7D%7B2%7D%20%5Cright%29%3Db%5Cimplies%20-1%2B%5Ccfrac%7B7%7D%7B2%7D%3Db%5Cimplies%20%5Cblacktriangleright%20%5Ccfrac%7B5%7D%7B2%7D%3Db%20%5Cblacktriangleleft%20%5C%5C%5C%5C%5B-0.35em%5D%20%5Crule%7B34em%7D%7B0.25pt%7D%5C%5C%5C%5C%20~%5Chfill%20y%3D-%5Ccfrac%7B1%7D%7B2%7Dx%5E2%2B%5Ccfrac%7B5%7D%7B2%7Dx-7~%5Chfill)
