First question:
4(3x-5) + (2x -2)(4 + 3x-5)
Simplify -----> 12x - 20 + (2x-2)(3x-1)
Multiply the second part -----> 12x - 20 + 6x^2 -8x + 2
Combine like terms --------> 6x^2 + 4x - 18
Each side of the addition sign represents one of the rectangles above which is then added to get the area of the entire figure.
Second question:
The average is the summation of each data value divided by the number of data values. So it would be
(4 + 5 + 9)/ 3
Simplify ------> 18/3
Divide --------> 6
11111111111111111-111111111-1
All you do is solve for z. So 8z-13=7. To solve for a variable you have to do the opposite to cancel out the numbers on each side. First you add 13 over to 7 to cancel out 13 on the z side. So 8z=20 is what you have left. Then you divide 8 on both sides to cancel out 8 on the z side. what you are left with is z=2.5. Lastly you plug and check. 8(2.5) - 13 = 7, 20-13=7. And thats correct so z is 2.5.
(12,756 kilometers) - (4,879 kilometers) = 7,877 kilometers
1. 1/a^8 (Sorry I can't find out what the others are)
