Answer:
x = 15m
Step-by-step explanation:
The second triangle (large) is 3 times greater than the first triangle (small).
6 x 3 = 18 4 x 3 = 12 5 x 3 = x
5 x 3 is 15, so x is 15m
0.4(420) = 4(420)/10
(0.4 is essentially 4/10)
1680/10 = 168
There are 168 sixth graders
So you need to isolate the N right?
So what you want to do is add -3/5 to both sides to remove it from the left side. making it
2n=5+3/5 now all you need to do it isolate the N by divinding it by 2 on each side
n=5+3/5
/2
the 5+3/5 is divided by 2.
so N equales 5+3/5----/2
