The answer is BC = 38.22 cm.
<u>Step-by-step explanation</u>:
We have, ∠BKD = 120° ,BK = 28 cm, Draw a perpendicular from point K on BC let it intersect at point M. In right angled ΔBMK, ∠BKM=30° and BK = 28 cm
sin30° = perpendicular/hypotenuse
1/2 = BM/BK
1/2 = BM/28
BM= 14 cm
Now , In right angled ΔBMK ,
cos30° = base/hypotenuse
√3/2 = MK/28
MK = 14√3 = 24.22 cm
KMCD is a square MK = MC = 24.22 cm
also, BC = BM + MC , putting values of BM & MC we get :
BC = 14 cm + 24.22 cm
BC = 38.22 cm.
To determine this you could think of it in a couple ways.
1. If it takes 1/10 of a bag of fertilizer to put around 1 tree, he can fertilize 10 trees with 1 bag because there are 10 groups of 1/10 in a bag. Take 10 x 40 because there are 40 bags and get 400 trees to be fertilized.
2. You can divide 40 by 1/10 as the other strategy.
This is the same as 40 x 10/1.
Also equaling 400 trees that can be fertilized.
2.418 x 10^8 is the answer.
<span>Look at your table for a Z value of 1.55. The numbers on the far left column are your z values. See the 1.5 row, then move over to the 0.05 column to make it 1.55.
You'll see 0.9394.
That's the area under the normal curve from 1.55 to negative infinity.
But you wanted the area under the curve greater than 1.55.
Take 1-0.9394=0.0606.
You subtract from 1 because you know that the area under the whole curve is 1, so it gives you the area you need.</span>
1) 2x² -5x+12
2) x² +7x+10
3) 3x² +5x-2
