Answer:
Step-by-step explanation:
For A, 7x=21, it is asking, 7 multiplied by what number is 21? We can try to figure it out. Let's start with 0.
7(0)≠21
Then 1.
7(1)≠21
7(2)≠21
7(3)=21
Therefore, for question a, the answer is 3.
For question b, it's asking 6 minus what is 2.
With this one, we can say it is 4, since 6-4=2.
Now moving on to B.
a) 2x+4=16
We need to isolate x in order to find it's value.
So we can begin with subtracting 4 from both sides, getting us:
2x=12
Then, if we divide both terms by 2, we get x.
x=12/2
x=6.
b)
3 x (z/4)=9
Again, we need to isolate z.
So, we multiply both sides by 4, getting us
3z=36
then we divide by 3
z=36/3
z=12
c) 16-x=2
Here we simply subtract 16 from each side, then flip the signs to get positive x.
So, 16-x=2
-x=-14
x=14
d) 4k=20
This is essentially asking, 4 times what number is 20?
So we can divide both sides by 4 and get
k=20/4
k=5
