A, C, and E.
you can check them by putting into y=mx+b form. if m is negative then as domain increases range decreases.
1) x+y=302x+9y=172x=-y+30-2y+60+9y=1727y=112y=16x=14
14 2-point questions and 16 9-point questions
2) c+a=163
6c+13a=1566
c=-a+163
-6a+976+13a=1566
7a=588
a=84
c=79
84 adult tickets and 79 children tickets
3) a+c=15; ax+cy=132
8+7=15; 8x+7y=132
a+c=9; ax+cy=72
4+5=9; 4x+5y=72
8x+7y=132
4x+5y=72
(8x+10y)=(144)
8x=-7y+132
8x=-10y+144
-7y+132=-10y+144
3y=12
y=4
4x+20=72
4x=52
x=13
The price for an adult ticket is $13 and the price for a child ticket is $4
The width of a book is 1.5 inches.
The total width of 79 books is 1.5×79
= 118.5 inches.
The cost of a 34.5 inch wide shelf is $12.95
Therefore, the cost of a 118.5 inch wide shelf will be:
(Let the cost of the 118.5 inch wide shelf be x)

x= $44.48
<span>The given condition is:
If 5x + 7 = 2x =1, then 3x + 7 = -1
=> This given equation represent a
subtraction property of equality.
=> 5x +7 =2x-1
=> 5x – 2x + 7 = -1
=> 3x + 7 = -1
What we did was we subtracted 2x from 5x
to get the 3x
Subtraction property of equality is a mathematical process in where we subtract
numbers from both sides that contains the same expression.
Like 5x and 2x, since they have the same equation, we both subtracted both
numbers and the rest remains as it is.
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