Charles is saving $5 each week. he earns an extra $15 by mowing his neighbors lawn. how many weeks does he need to save in order to get $75

Hey there!!

Given amount of information:

With this given information, we get to know that the number 15 is a constant and we don't know the number of weeks. Hence, it is a variable.

Let's take the number of weeks as 'w'

Let's now form a equation.

... 5w + 15 = ?

The total amount we want is $75. Hence,

... 5w + 15 = 75

... 5w + 15 - 15 = 75 - 15

... 5w = 60

... 5w/5 = 60/5

... w = 12

Hence, the number of weeks is 12.

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!

answer: this is not a question

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