-30 is the answer
-6+4(-6)
-6+(-24)
-30
Let's say you had a cake that is cut into 5 equal slices. Then someone eats 2 of those slices. They ate 2/5 of the cake.
Now let's say you have another cake that you cut into 10 equal slices. If someone eats 4 of those ten, then they have eaten 4/10 = 2/5 of the cake.
Check out the diagram below to see a visual of how 4/10 and 2/5 are equivalent fractions.
Going from 2/5 to 4/10 has us multiply top and bottom by 2.
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Similarly, 1/2 = 5/10 after multiplying top and bottom by 10
The original expression 2/5 + 1/2 turns into 4/10 + 5/10
Then you add the numerators to get 4+5 = 9, placing that over the common denominator of 10
<h3>Answer: 9/10</h3>

part B)
the slope is always in a linear equation, the coefficient of the independent variable, in this case namely "35".
35 or 35/1 dollars/day means
for every passing day the car is rented out, the charge is $35, so if you rent the car "d" days, you'll be charged 35d.