First off, let's take a look at what these numbers are:
Real numbers: It can be any numbers,both rational and irrational.
Natural numbers: The number has to be integer and positive.
Integers: A number without fraction or demical place.
Whole number: The number has to be natural and cannot be negative.
Therefore, as 12 is a positive number with no demical place or fraction, it is real numbers,integers, whole numbers, and natural numbers.
Hope it helps!
A) 4(25-3y)+5y=9
100-7y=9
91=7y
y=13
(-14,13)
b) 14-x=x-10
2x=24
x=12
(12,14)
c) 4x=12
(3,7)
d) 18.5x+10.4y=200
x+y=130
A=h(b+c)
A/h=b+c
b=(A/h)-c
Answer: b=(A/h)-c
4.74/.06=79
19.44/.54=36
I used a calculator. You can change each decimal into a fraction to solve too.
