Answer:
-3/2
Step-by-step explanation:
y2-y1/x2-x1
7-4/3-5
3/-2
-3/2
To find the surface area, you need to do the following:
A side of the figure is a trapezoid, so you should do 13+5x7 (since there are 2 of the same sides there is no need to divide by two.) and it should equal 126. To find the area of the top of the figure, you need to do 5x2 which equals 10. The area of the bottom of the figure is 26 (13x2), then do 2x3x2 to get the sides on the left and right of the figure. After all of this, add them together. (126+10+26+12=174.)
The surface area should be 174mm.
X = 97
Working on other question.
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.
Answer = B = 376 degrees - 3x