C= 8x + 5y
y-number of child tikets
C-8x= 5y
(C-8x)/5 =y
First option from up to down
39×2÷6=13
13-5=8 mm. The other base of the trapezoid is 8 mm. Let check it:
1/2(8+5)×6
=1/2×13×6
=39 square mm. Hope it help!
Answer: Choice B
(-2, 5)
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Explanation:
The original system is

Multiply both sides of the second equation by 3. Doing so leads to this updated system of equations

Now add straight down
The x terms add to -4x+3x = -1x = -x
The y terms add to 3y+(-3y) = 0y = 0
The terms on the right hand sides add to 23+(-21) = 2
We end up with the equation -x = 2 which solves to x = -2
Now use this to find y. You can pick any equation with x,y in it
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-4x+3y = 23
-4(-2)+3y = 23
8+3y = 23
3y = 23-8
3y = 15
y = 15/3
y = 5
Or
x-y = -7
-2-y = -7
-y = -7+2
y = -5
y = 5
Either way, we get the same y value.
So that's why the solution is (x,y) = (-2, 5)
Answer:
2.5
Step-by-step explanation:
Put the values in place of the corresponding variables and do the arithmetic:
ab - 0.5b = (1)(5) -0.5(5) = 5 - 2.5 = 2.5