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Answer:
F. x ≤ -5
Step-by-step explanation:
Translating the diagram to more conventional symbols, we have ...
4x +12 ≤ -8
4x ≤ -20 . . . . . . . subtract 12 from both sides
x ≤ -5 . . . . . . . . . divide both sides by 5
1 in 13 or 1/13 because those are the only numbers it gives you and since he only sold one vanilla cone in the last thirteen cones you can only assume that he sells one vanilla every 13
3 cm on the map represents 31.5 km in reality.
3cm : 31.5 km
1cm : 31.5/3 km
1cm : 10.5km
So the scale on the map is 1cm represents 10.5 km.
Answer: B. y=9
Explanation: divide both sides of the equation by three
y3/3 = y
27/3=9
y=9
hope this helps:)
We can use linear combinations of the equations to eliminate variables.
3x - 4y = 1
-2x + 3y = 1
To eliminate y we'll make the linear combination of 3 times the first equation minus four times the second.
9x - 12y = 3
-8x + 12y = 4
Adding,
x = 7
We could solve for y directly but let's use another linear combination, twice the first plus three times the second:
2(3x - 4y) + 3(-2x + 3y)= 2(1)+3(1)
y = 5
Check: 3(7)-4(5)=1 good. -2(7)+3(5)=1 good.
Q18 Answer: (7,5)
y = -3x + 5
5x - 4y = -3
4y +1(5x - 4y) = 4(-3x + 5) + 1(-3)
5x = -12x + 20 -3
17 x = 17
x = 1
y = -3(1) + 5 = 2
Check: 5(1) - 4(2) = -3 good
Q19 Answer (1,2)
6x + 5y = 25
x = 2y + 24
6x = 12y + 144
5y = 25 - 12y - 144
17y = -119
y = -119/17= -7
x = 2y+24= 10
Check: 6(10)+5(-7)=25 good 2y+24=2(-7)+24=10=x good
Q20 Answer (10,-7)
3x + y = 18
-7x + 3y = -10
9x + 3y = 54
9x - -7x = 54 - -10
16x = 64
x=4
y = 18 -3x = 18-12=6
Check: 3(4)+6=18 good, -7(4)+3(6)=-10 good
Q21 Answer: (4,6)
