Answer:
i hope this helps! :)
Step-by-step explanation:
1.) 130
2.) 56
3.) 5
4.) 10
5.) 24
6.) 91
Get the x terms by themselves on one side and a constant on the other side of the equal sign...
4x^2-8x=1 make the leading coefficient equal to one...
x^2-2x=1/4 now halve the linear coefficient, -2 in this case, square it, and add that value to both sides of the equation...-2/2=-1, -1^2=1 so
x^2-2x+1=1+1/4
x^2-2x+1=5/4 now the left side is a perfect square...
(x-1)^2=5/4 take the square root of both sides...
x-1=±√(5/4) add 1 to both sides
x=1±√(5/4)
7^2 - 3 + 9 x 8 / 2
49 - 3 + 9 x 8 / 2
49 - 3 + 72/2
49 - 3 + 36
46 + 36
82
w = 82
Mrs. Smith donated $20
The constant proportionality is $1 because no matter what, Mrs. smith will donate $1 for each mile. So if Sam were to only walk 1 mile, mrs. smith would donate $1. Or seen as a 1:1 proportion.
The first pipe fills 1/8 of a pool in one hr.
The second pipe fills 1/4 of a pool in one hr.
(1/8+1/4)2= 3/4 done by the first two pipes in 2 hours.
Therefore the last pipe must do 1 1/4 of the filling in 2 hours, which is 5/8 per hour.
5/8x=1
x=8/5
It takes the third pipe 1 hour and 36 minutes to fill it by itself.