20 ÷ 2 (5,5)
20 ÷ 2 (25)
20 ÷ 50
.4
        
             
        
        
        
Answer:
(2,-1)
Step-by-step explanation:
Multiply first equation by 2:
10x + 2y = 18
Subtract the second equation from this so that the 2y terms cancel:
10x - 3x = 18 - 4
7x = 14
x = 2
Plug into first equation to find y:
5(2) + y = 9
10 + y = 9
y = -1
The answer is (2,-1)
 
        
                    
             
        
        
        
Step-by-step explanation:
Total amount of cookies = 4250
butter cookies, b 
Almond cookies, a
Chocolate cookies, c 
It made 715 more butter cookies than
almond cookies
b = a + 715
It made 5 times as many chocolate cookies as almond
5a = c
Total amount of cookies
= a + b + c
= a + (a+715) + (5a)
= 7a + 715
7a + 715 = 4250
7a = 4250-715
a = 3535 / 7
a = 505
c = 5a
 = 5 (505)
 = 2525
The factory make 2525 chocolate cookies.
 
        
             
        
        
        
49^2 or 7 I just know from 6th grade
        
             
        
        
        
Since they want only the coordinates of the vertices. You only care about where the lines intersect, the greater than, less than signs are irrelevant.
Get each equation in 'y=mx+b' form
1)  y = -x + 9
2)  y = 2x-21
3)  y = -4x +15
Now you can set any 2 equations equal to each other and solve for 'x'.
This will be the 'x' coordinate of the point where the 2 lines intersect.
You need 3 points, so you will need 3 different sets of 2 equations:
1) = 2)
2x -21 = -x+9
3x = 30
x = 10  -----> y = -(10)+9 = -1
1) = 3)
-x+9 = -4x+15
3x = 6
x = 2  -------> y = -(2) + 9 = 7
2) = 3)
2x - 21 = -4x+15
6x = 36
x = 6  ---------> y = 2(6) -21 = -9
Therefore the 3 intersecting points are:
(10,-1)
(2, 7)
(6, -9)