Question

Part A: Solve –mk – 90 > 85 for m. Show your work. (4 points) Part B: Solve 3c – 5f = 55 for f. Show your work. (6 points)

Answer 1

A: mk < -175 if k >0, then m < -175/m, if k = 0, no answers, if k < 0, then m > -175/m

B: 5f = 3c-55, then f = 3c-55/5

Answer 2

(A)

Solve:
`-mk-90>85` for m; .....[1]

Addition property of equality states that you add same number to both sides of an equation

Add 90 to both sides in [1], we get;

-mk-90+90 > 85+90

Simplify:

-mk>175 or

Now, divide both sides by -k.

`m< -(175)/(k)`

Also remember, that when you divide or multiply a number in an inequality, you must flip the sign to its opposite.

Therefore, the value of
`m< -(175)/(k)` for k≠0.

(B)

Solve: 3c-5f=55 for f;

Subtract both sides by 3c we get;

3c-5f-3c=55-3c

Simplify:

-5f= 55-3c

Divide both side by -5 we get;

`(-5f)/(-5)= (55-3c)/(-5)`

Simplify:

`f=(x)/(y) =(55)/(-5)- (3c)/(-5)`

or

`f=-11+(3c)/(5)`

Therefore, the value of
`f=-11+(3c)/(5)` for every c.