math questions really need help?

Question

hi i have homework and im really stuck on these 3 math questions, the others i got perfect except for these. these 3 math equations are two step equations.

-2k divided by 7 = 36. 5 + r divided by -2 = -6
and
f - 6 divided by 5 = 3.2 thanks for helping!

Answer 1

In all cases you need to get rid of the fraction first. Multiply both sides by the denominator, then go from there:

PROBLEM 1:
-2k / 7 = 36

Multiply both sides by 7:
-2k = 36 * 7
-2k = 252

Divide both sides by -2:
k = 252/-2
k = -252/2
k = -126

PROBLEM 2:
(5 + r) / -2 = -6

Multiply both sides by -2:
5 + r = -6 * -2
5 + r = 12

Subtract 5 from both sides:
r = 12 - 5
r = 7

PROBLEM 3:
(f - 6) / 5 = 3.2

Multiply both sides by 5:
f - 6 = 3.2 * 5
f - 6 = 16

Add 6 to both sides:
f = 16 + 6
f = 22

Answer 2

-2k/7 = 36.5

Multiply both sides by 7 to get rid of the fraction

-2k = 255.5

Divide by -2 to get the k alone

k = -127.75

2) 5 + r/-2 = -6
Multiply both sides by -2 to get rid of the fraction

-10 + r = 12

Add 10 to both sides to get r alone

r = 22

3). f - 6/5 = 3.2

Multiply both sides by 5 to get rid of the fraction

5f - 6 = 16

Add 6 to both sides to get 5f alone

5f = 22

Divide both sides by 5 to get f alone

f = 22/5
f = 4.4

Hope this helps

Answer 3

-2k/7 = 36..............xly each side by 7:

-2k = 252................divide each side by -2:

k = -126.

(5+r)/-2 = -6.............xly each side by -1:

(5+r)/2 = 6.................xly each side by 2:

5 + r = 12..................take 5 from each side:

r = 7.

(f-6) /5 = 3.2..............xly each side by 5:

f - 6 = 16................add 6 to each side:

f = 22.

Hope this helps, Twiggy.