The zero product property tells us that if we have
xy=0, then we can assume that x and y both equal 0
so
(4k+5)(k+7)=0
we can assume that 4k+5=0 and k+7=0
so
4k+5=0
minus 5 both sides
4k=-5
divide both sides by 4
k=-5/4
k+7=0
minus 7 both sides
k=-7
k=-5/4 or -7
Answer:
she should leave 4.05
Step-by-step explanation:
becuase 15% of 27 is 4.05
For this case we have the following variables:
x: number of hours that it takes Mr. David to complete a job working alone.
y: number of hours it takes Mr. Ludwing to complete a job working alone.
k: number of hours it takes for both of them to do a job working together.
We now write the equation that models the problem.
To do this, we must add the work rate per hour of each and equal to the rate of work per hour of both.

We have then:
Answer:
The algebraic expression that models the problem is:
