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 ![\frac{32}{5-\sqrt{7}}](https://tex.z-dn.net/?f=%5Cfrac%7B32%7D%7B5-%5Csqrt%7B7%7D%7D)
According to him,
![\frac{32}{5-\sqrt{7} = \frac{32(5+\sqrt{7}{(5-\sqrt{7})(5+\sqrt{7}](https://tex.z-dn.net/?f=%5Cfrac%7B32%7D%7B5-%5Csqrt%7B7%7D%20%3D%20%5Cfrac%7B32%285%2B%5Csqrt%7B7%7D%7B%285-%5Csqrt%7B7%7D%29%285%2B%5Csqrt%7B7%7D)
Solving the nominator and denominator
![= \frac{160-32\sqrt{7}}{25+5\sqrt{7}-5\sqrt{7}-7}](https://tex.z-dn.net/?f=%3D%20%5Cfrac%7B160-32%5Csqrt%7B7%7D%7D%7B25%2B5%5Csqrt%7B7%7D-5%5Csqrt%7B7%7D-7%7D)
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.
$15 + $32.50 + 8% = $51.30
15 + 32.50 = 47.50
8% × 47.50 = 3.80
47.50 + 3.80 = 51.30
Step-by-step explanation:
(x × 5) +6=41
5x + 6=41
5x =41-6
5x=35
x=(35/5)
x=7
Answer:
2 2/5
Step-by-step explanation:
divide 12 into 5 you get 2.4
2.4 is the same as 2 4/10 which can be equal to 2 2/5
Answer:
y = -6
x = 1
Step-by-step explanation:
-x + 2y = -13
-x - 2y = 11
Sum the equations:
-x -x = -2x
+2y - 2y = 0
-13 + 11 = -2
then
-2x = -2
x = -2/-2
x = 1
from the first eq.
-x + 2y = -13
-1 + 2y = -13
2y = -13 + 1
2y = -12
y = -12/2
y = -6
check:
from the second eq.
-x -2y = 11
-1 -(2*-6) = 11
-1 -(-12) = 11
-1 + 12 = 11