Yes and for a. You can just put y=x [y=1x is bascually the same but just the 1 isnt needed]
This problem is fairly simple if you know the exponential equation, you start with y=78(.17)^x. the you put 10=78(.17)^x, then you solve for x
10=78(.17)^x
-78
-68=.17^x
divide .17 then you have your answer!!
So based on the given problem above, it says that, for one batch with 3/4 cup of brown sugar can make 6 dozen big cookies. If we are to make 15 dozen cookies, what we need to do is to divide 3/4 cup of brown sugar by 6 dozen, and we get 0.125. This means that per dozen, it is equivalent to 0.125 cup of brown sugar. If we multiply it by 15 dozens, we get 1.875 cup or 1 and 7/8 cup of brown sugar. Hope this answer helps.
So the answer to this equation is 9
to find the answer we first need to substitute the x for 1
so the equation would be 4×1^2+5*1
so now we simplify the equation so it would be 4+5×1
and 4+5*1 simplified is 4+5
and 4+5=9