Answer:
54.50
Step-by-step explanation:
10 * 5 + 9%
50 + 9% (4.50) = 54.50
<h3>
Answer: 20</h3>
Explanation:
For any rectangle, the diagonals are the same length.
AC = BD
7x-35 = 3x+45
7x-3x = 45+35
4x = 80
x = 80/4
x = 20
Give me a second to get the answer and I’ll text you back
In both problems, the sum of side lengths is the perimeter. Opposite sides of a parallelogram (or rectangle) are equal in length, so you can find the perimeter by doubling the sum of adjacent sides.
25. 2(x +(x +15)) = (x +45) +(x +40) +(x +25)
.. 4x +30 = 3x +110 . . . . . . . . . . . . . . . . . . . . . . simplify
.. x = 80 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . subtract 3x+30
.. 4x +30 = 4*80 +30 = 240
The perimeter of each is 240 units.
26. 2(x +(x +2)) = (x) +(x +6) +(x +4)
.. 4x +4 = 3x +10 . . . . . . . . . . . . . . . . . . . . . . simplify
.. x = 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . subtract 3x+4
.. 4x +4 = 4*6 +4 = 28
The perimeter of each is 28 units.
A) The first step needs 100 bricks, the second needs 98, the third needs 96, and so on. Therefore the number of bricks for the nth step is: a_n = a_1 + d(n-1), where a_1 = 100 (the first term), d = -2 (difference).
a_n = 100 - 2(n-1) = 102 - 2n, and for the 30th step, a_30 = 102 - 2*30 = 42. So the top step will need 42 bricks.
b) The total staircase will need: 100 + 98 + 96 + ... + 44 + 42, and there are n = 30 terms. Using the formula for the sum of an arithmetic sequence:
S = (a_1 + a_n)*n/2 = (100 + 42)*30/2 = 2130
Therefore, 2130 bricks are required to build the entire staircase.
