50 points for anyone who can check my practice quiz !
solve: 10 – 5m = 25
7
3
–7
–3
solve: 3n + 7 = 28
63
7
–7
solve: 5y + 1.8 = 4y – 3.2
–1.4
–5
solve v = ℓwh for w.
w = vℓh
the sides of a rectangle are in the ratio 3: 2. what is the length of each side if the perimeter of the rectangle is 55 cm?
11 cm, 11 cm, 16.5 cm, 16.5 cm
5.5 cm, 5.5 cm, 11 cm, 11 cm
20.4 cm, 20.4 cm, 30.6 cm, 30.6 cm
22 cm, 22 cm, 33 cm, 33 cm
solve: 10(1 – 2y) = –5(2y – 1)
solve: 43 – 3d = d + 9
17
–26
–13
two planes leave an airport the same time and travel in opposite directions. one plane averages 300 miles per hour, and the other plane averages 600 miles per hour. when will they be 2700 miles apart?
2.25 hr
3 hr
7 hr
4.5 hr
solve: 4(k + 5) = 2(9k – 4)
–2
2
solve s = 2πrh for r.
r = 2sπh

10 – 5m = 25
10 - 25 = 5m
-15 = 5m
m = -15/5
m = -3
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3n + 7 = 28
3n = 28 - 7 
3n = 21
n = 21/3
n = 7
------------------------------

5y + 1.8 = 4y – 3.2
5y - 4y = -3.2 - 1.8
y = -5
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Solve V = ℓwh for w

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The sides of a rectangle are in the ratio 3:2. What is the length of each side if the perimeter of the rectangle is 55 cm?

length=3x
width=2x

2(3x + 2x) = 55
2(5x) = 55
10x = 55
x = 55/10
x = 5.5

length= 3x = 3 * 5.5 =  16.5
width= 2x = 2 * 5.5 = 11

 11 cm, 11 cm, 16.5 cm, 16.5 cm
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43 – 3d = d + 9
43 - 9  = d + 3d
34 = 4d 
d = 34/4
d = 8.5
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Two planes leave an airport the same time and travel in opposite directions. One plane averages 300 miles per hour, and the other plane averages 600 miles per hour. When will they be 2700 miles apart?

2700 / (300+600) = 2700 / 900 = 3 hr
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4(k + 5) = 2(9k – 4)
4k + 20 = 18k - 8
20 + 8 = 18k - 4k
28 = 14k
k = 28/14
k = 2
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Solve S = 2πrh for r.