Answer:
5.45 hours or 5 hours 27 minutes to nearest minute.
Step-by-step explanation:
We work in rates per hour.
Kevin does 1/10 of the roof in an hour and Sam does 1/12 of the roof/hour.
Now we add to get the equation:
1/10 + 1/12 = 1 / x where x is the time they take to repair the roof working together.
Multiplying through by the LCM 60x:
6x + 5x = 60
11x = 60
x =60/11
x = 5.45 hours.
Plug in for x.
7(2y - 4) + 5y = -66
14y - 28 + 5y = -66
19y - 28 = -66
19y = -38
y = -2
Put it back into the equation.
2(-2) - 4 = -8
x = -8
The x-value is x = -8
Answer:
5
Step-by-step explanation:
(-4)(5) = -20
Scale factor is 2
30/15 = 2
20/10 = 2