Answer:
Noah mistakenly added 25 and 7 in denominator instead of subtracting in the third step.
Step-by-step explanation:
Noah had to rationalize the denominator of 
According to him,

Solving the nominator and denominator

Noah did correctly till this point.
In the next step he add 25 and 7 in the denominator, whereas, it should be subtracted.
Hence,
Noah mistakenly added 25 and 7 in denominator instead of subtracting in the third step.
Unit fractions are fractions with a 1 as the numerator(number on top)
so 3/8 equals 1/8+1/8+1/8
3/5 is smaller. if you look at the ruler 3/5 will be first and then 3/8th
Answer:
a = -2
b = 1
c = 5
Step-by-step explanation:
Given:
2a + 4b + c = 5 ............(1)
a - 4b = - 6
or
a = 4b - 6 .............(2)
2b + c = 7
or
c = 7 - 2b ...........(3)
substituting 2 and 3 in 1, we get
2(4b - 6 ) + 4b + (7 - 2b) = 5
or
8b - 12 + 4b + 7 - 2b = 5
or
10b - 5 = 5
or
b = 1
substituting b in 2, we get
a = 4(1) - 6
or
a = -2
substituting b in 3, we get
c = 7 - 2(1)
or
c = 5
thus,
a = -2
b = 1
c = 5