Answer:
x=7cm.
Step-by-step explanation:
A=1/2(a+b)h.
63=1/2(6+12)x.
63=1/2(18)x.
63=9×x.
63/9=9×x/9.
7cm=x.
x=7cm.
Step-by-step explanation:
first you should check whether the sequence is arithmetic and geometric .as you see the sequence is arithmetic with the common difference of -16384.
Answer:
-43
Step-by-step explanation:
1. -3 x -3 x -3 = -27
2. -27- 4 x 4
3. -27- 16 = -43
Let h be the height of the tree and d the distance to the top of the tree from the point on the ground. Draw a diagram to visualize the situation:
Since the distance to the top of the tree is 11 ft more than two times the height, then:

Use the Pythagorean Theorem to relate the length of the sides of the right triangle:

Notice that we have obtained a quadratic equation in terms of h. Write it in standard form and use the quadratic formula to solve for h:

Since the height of the tree must be positive, the only solution is h=39ft. To the nearest foot, the height of the tree is 39.
Therefore, the height of the tree is 39 ft.
<span>Arrange the first row arbitrarily: 1 2 3 4.
Then there is only one option to begin the next row: 3.
The remaining row must be 4 1 2.
This leaves no options for beginning the third row (1 and 3 are in the same column, and 2 and 4 share the diagonal).</span>