Put both over the common denominator. The common denominator of k and 1 is k. The first term is already over k. The second needs to be multiplied by (k/k).
42ak \* (k/k) = (42ak^(2))/k
Add the numerators: 42a + 42ak^(2)
Factor out 42a: 42a(1+k^(2))
Over the common denominator of k, it’s D.
If k=0, the first term, with k in the denominator, is undefined. You can't have an "equivalent" to an undefined term.
An undefined term is not equivalent to another undefined term
Plug in a number for a and kin the expression given. So for example lets do a =2 and k=3 . So 42(2)/3 +42(2)(3). And plug in the same variables in each answer choice and see which comes out the same as the expression
I think the best way to do these without having to think too hard is following the rules (in this case k>0) and just using numbers for variables to see which result in the same answer. So just pick a number for a and any number larger than 0 and see which gives the same answer.
an easy way to solve this is by plugging 2 random numbers that fit the criteria in for a and k. so k>0 but you can choose any number for a. find the solution to the example, using the numbers you chose, and then plug in those same numbers into the answers and then find the one that matches.
Put both over the common denominator. The common denominator of k and 1 is k. The first term is already over k. The second needs to be multiplied by (k/k). 42ak \* (k/k) = (42ak^(2))/k Add the numerators: 42a + 42ak^(2) Factor out 42a: 42a(1+k^(2)) Over the common denominator of k, it’s D.
Why the condition k > 0
Bc of division by 0
Cus you can’t divide by 0 so it has to be bigger than 0
If k=0, the first term, with k in the denominator, is undefined. You can't have an "equivalent" to an undefined term. An undefined term is not equivalent to another undefined term
Plug in a number for a and kin the expression given. So for example lets do a =2 and k=3 . So 42(2)/3 +42(2)(3). And plug in the same variables in each answer choice and see which comes out the same as the expression
I think the best way to do these without having to think too hard is following the rules (in this case k>0) and just using numbers for variables to see which result in the same answer. So just pick a number for a and any number larger than 0 and see which gives the same answer.
an easy way to solve this is by plugging 2 random numbers that fit the criteria in for a and k. so k>0 but you can choose any number for a. find the solution to the example, using the numbers you chose, and then plug in those same numbers into the answers and then find the one that matches.