Answer:
x = 2.5 inches. Or
x = 5/2
Step-by-step explanation:
Length: 7 + 2x
Width: 5 + 2x
Note that you have to add x at each end of the picture and onto each part of the width.
The entire area is 120 square inches.
Formula
L*W = Area
(2x + 7)(2x + 5) = 120
Solution
4x^2 + 10x + 14x + 35 = 120 Subtract 120 from both sides. Add xs
4x^2 + 24x + 35 - 120 = 0
4x^2 + 24x - 85 = 0 Factor
(2x + 17)(2x - 5)
2x + 17 has no meaning. It will give - 8.5 which is not possible.
2x - 5 =0
2x = 5 Divide by 2
x = 5/2
x = 2.5
Note: I don't know which one the computer is looking for.
40 + 60 = 100
Hundrends place
Answer:
addition
Step-by-step explanation:
18 (<u> d </u> - 9 ) = 198
3
divide both side by 18
<u> d </u> - 9 = <u> 198 </u>
3 18
<u> d </u> - 9 = 11
3
multiply both sides by 3
d - 27 = 33
add 27 to both sides
d = 33 + 27
lastly, add them together
d = 60
therefore, the last step is addition
Let's start by visualising this concept.
Number of grains on square:
1 2 4 8 16 ...
We can see that it starts to form a geometric sequence, with the common ratio being 2.
For the first question, we simply want the fifteenth term, so we just use the nth term geometric form:


Thus, there are 16, 384 grains on the fifteenth square.
The second question begs the same process, only this time, it's a summation. Using our sum to n terms of geometric sequence, we get:



Thus, there are 32, 767 total grains on the first 15 squares, and you should be able to work the rest from here.
Answer: 228.01 pi and the second is near 715. 9514
Step-by-step explanation: area of a circle is pi times the radius squared. Radius is half a diameter. Half of 30.2 is 15.1. 15.1 squared is 228.01. If you use 3.14 in place of pi, and multiply that to 228.01 you get 715.9514. I think