The inequality should be

The sign on the right is only a 'smaller than' sign because he spent less than 180.
On the left, assuming that even if Calvin took nobody (poor Calvin), we should assume that he at least went himself, hence he spent a minimum of $12.
510 would be your answer. I hope this helped! :)
Answer:
A
Step-by-step explanation:
The student must have thought that every single arrowhead is a line of symmetry, so since there are 10 arrowheads, there must be 10 lines of symmetry. This is incorrect because if you look closely at the diagram, each line has 2 arrowheads, so the student is overcounting by a factor of 2. They should have just counted the number of lines, not arrowheads. Therefore, there must be 10/2 = 5 lines of symmetry, not 10. Hope this helps!
<h3>
Answer:</h3>
- -100x +100; 3
- 5x +81; 162
<h3>
Step-by-step explanation:</h3>
The distributive property is your friend. It tells you ...
a(b + c) = ab + ac
It can also be used to simplify the product of binomials (or other polynomials).
(a +b)^2 = (a +b)(a +b) = a(a +b) + b(a +b) = a^2 +ab +ab +b^2
(a +b)^2 = a^2 +2ab + b^2 . . . . . . . worth remembering
1. (x -10)^2 -x(x +80) = (x^2 -20x +100) +(-x^2 -80x)
= -100x +100 . . . . . . simplified form
For the purposes of calculation, it can be easier to factor out 100:
= 100 (1 -x)
Then for x = 0.97
= 100(1 -0.97) = 100(0.03) = 3
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2. (2x +9)^2 -x(4x +31) = (4x^2 +36x +81) -4x^2 -31x = 5x +81
For x = 16.2, this is ...
5(16.2) +81 = 81 +81 = 162
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The purpose of the attachment is to show the evaluation is correct.
1x + 3y = 5
<u>2x - 3y = 1</u>
<u>3x</u> = <u>6</u>
3 3
x = 2
2(2) - 3y = 1
4 - 3y = 1
<u> -4 -4</u>
-<u>3y</u> = <u>-3</u>
-3 -3
y = 1
(x, y) = (2, 1)