If the sale price is 30%, you turn that into a decimal and it will be .3. now you multiply the discount by 39 and it will get you 11.7. 11.7 is the money of discount so now all you have to do is subtract 11.7 from 39 and you shall get 27.3.
I think this is what you are looking for:
=−12
a
b
=
−
12
+=4
a
+
b
=
4
(+)2=42
(
a
+
b
)
2
=
4
2
2+2+2=16
a
2
+
b
2
+
2
a
b
=
16
∴2+2=16+2×12=40
∴
a
2
+
b
2
=
16
+
2
×
12
=
40
Now, (−)2=2+2−2=40+2×12=64
(
a
−
b
)
2
=
a
2
+
b
2
−
2
a
b
=
40
+
2
×
12
=
64
∴(−)=64‾‾‾√=±8
∴
(
a
−
b
)
=
64
=
±
8
So, 2−2=(+)(−)
a
2
−
b
2
=
(
a
+
b
)
(
a
−
b
)
2−2=(4)(±8)=±32
a
2
−
b
2
=
(
4
)
(
±
8
)
=
±
32
Hope that helps and sorry if it is confusing!
Answer:
7. is 5 - 35n
8. is -6x - 24
9. is 15m - 30
10. is 24p - 28
11. is 5b - 5
12. 5x + 45
RULE:
WHEN MULTIPLYING TWO NEGATIVES YOU WILL GET POSITIVE.
IF ONE IS NEGATIVE AND THE OTHER IS POSITIVE WHEN MULTIPLYING IT WILL BE NEGATIVE.
WHEN MULTIPLYING TWO POSITIVE NUMBERS IT WILL ALWAYS BE POSITIVE
SAME THING IF YOU MULTIPLY A POSITIVE NUMBER WITH A NEGATIVE NUMBER YOU GET A NEGATIVE AS YOUR ANSWER
YOU NEED ONE SIGN OF THE SAME WHEN MULTIPLYING TO BE A POSITIVE AS YOUR ANSWER
YOU NEED ONE SIGN TO BE DIFFERENT FROM THE OTHER WHEN MULTIPLYING TO GET A NEGATIVE AS YOUR ANSWER
Each person will get 4.75 ounces of cake. You just divide 33 1/4 by 7.
Hope this helps! :D
~PutarPotato