Part A
The expression "ma" is the same as "m*a" (m times a). To isolate 'a', we divide both sides by m. Division is the inverse operation of multiplication. Think of it as undoing multiplication
F = ma
F = m*a
F/m = m*a/m
F/m = a
a = F/m
Answer: a = F/m
Note: the slash "/" without quotes means "divide"
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Part B
Use the result from part A. We will plug F = -24 and m = 10 into that equation
a = F/m
a = -24/10
a = -2.4
Answer: -2.4
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Part C
We will use the equation F = m*a
F = m*a
24 = m*12 ... plug in F = 24 and a = 12
24/12 = m*12/12
2 = m
m = 2
Answer: 2
First substitute .5x in for y to get a solvable equation. You should get 6x+8(.5x)=30. Then multiply 8 times .5 to get 6x+4x=30. Then combine like terms (6x+4x) to get 10x=30 and divide both sides by 10 to get x=3. Then plug this x value (3) into the other equation (y=.5x) to find the value of y. Y=.5(3) so y=1.5. Therefore the answer is B.
