Explanation:
question 1. Solve the equation 8-7/10 c = 6 - 1/5c for c
8 - 7/10c = 6 - 1/5c
subtract 8 from both sides:
8 - 7/10c - 8 = 6 - 1/5c - 8
- 7/10c = -2 - 1/5c
add 1/5c to both sides:
- 7/10c + 1/5c = -2 - 1/5c + 1/5c
- 7/10c + 1/5c = -2
change to common denominator:
- 7/10c+ 2/10c = -2
- 5/10c = -2
-1/2c = -2
multiply both sides by -2:
- 1/2c(-2) = -2(-2)
c = 4
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question 2. 75 - 3.5y - 4y = 4y + 6 for y
75 - 3.5y - 4y = 4y + 6
75 - 7.5y = 4y + 6
add 7.5y to both sides:
75 - 7.5y + 7.5y = 4y + 6 + 7.5y
75 = 11.5y + 6
subtract 6 from both sides:
75 - 6 = 11.5y + 6 - 6
69 = 11.5y
divide both sides by 11.5:
69/11.5 = 11.5y/11.5
y = 6
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Question 3. Solve the equation 16.5 + 2.75h = 9h + 7.5 − 4.25h for h.
16.5 + 2.75h = 9h + 7.5 − 4.25h
16.5 + 2.75h = 4.75h + 7.5
subtract 7.5 from both sides:
16.5 + 2.75h - 7.5 = 4.75h + 7.5 - 7.5
9 + 2.75h = 4.75h
subtract 2.75h from both sides:
9 + 2.75h - 2.75h = 4.75h - 2.75h
9 = 2h
divide both sides by 2:
9/2 = 2h/2
h = 9/2