Answer:
(6,-7)
Step-by-step explanation:
subtract them:
-8x - 5y = -13
-4x - 5y = 11
you get
-4x = -24
so x = 6
plug x into the second equation:
-24 - 5y = 11
-5y = 35
y = -7
so your solution is (6,-7).
Cobalt has an atomic number (Z) of 27, which means the nuclei of all its isotopes have 27 protons. Cobalt 60 has an atomic mass of 60, so it has 60-27 = 33 neutrons.
The mass of 27 isolated protons plus the mass of 33 isolated neutrons would be:
27*(1.007825 u) + 33*(1.008665 u) = 60.497220 u
The actual mass of the nucleus of 60-Co is 59.933820 u.
Mass defect: 60.497220 u - 59.933820 u = 0.563400 u
The mass defect is equal to the binding energy of a nucleus.
using the fact that 1 u = 931.5 MeV/c^2
(0.563400 u)*(931.5 MeV/u) = 524.807 MeV
The horizontal line has an equation: y = a, where a is any real number.
We know, the line passes through the point (-8, -7) → x = -8, y = -7.
<h3>Answer: y = -7</h3>
He needs 160 5-star reviews in a role. We can write a function to solve this problem. His current total stars is 4.4*160=704. Suppose he needs x more 5-star reviews, then his total stars will be 704+5x. 160+x is the new number of reviews, and the new average will be 4.7, so 4.7*(160+x)=704+5x. The solution is 160. Besides, if you want to get the answer really fast, you can see that 4.7 is right in the middle of 4.4 and 5, so you can immediately guess that the number of new 5-star reviews should be equal to the number of current reviews.
Answer: $ 82
Step-by-step explanation:
92 - 10 = 82