The answer should be the third one I believe
Answer:
Carter family = 25 hours
Davis family = 31 hours
Step-by-step explanation:
Let's say the number of hours the Carter family used their sprinkler is x and the number of hours the Davis family used their sprinkler for is y.
So combined:
x + y = 45 hours
and we are also told that:
40x + 15y = 1300 L
So we can do simultaneous equations to solve the problem.
With some rearranging, we can figure out that:
y= 45 - x
and by substituting that into the second equation:
40x + 15 (45 -x) = 40x + 675 - 15x = 1300L
25x = 1300 - 675
25x = 625
x = 25 = hours that the Carter family used their sprinkler
and we can substitute that back into the original equation to find how many hours the Davis family used their sprinkler so:
25 + y = 56
y = 31
The Davis family used their sprinkler for 31 hours whilst the Carter family used their sprinkler for 25 hours.
The exercise is basiacally asking for the perimeter of the garden. The perimeter of a rectangle is twice the sum of its dimensions, so we have
Answer:
A) Check the first two: 2(x+5) and 2(x) + 2(5)
B) Check the last one: 14y + 2
Answer:
A) a • (b • c) = (a • b) • c
Step-by-step explanation:
The associative property of multiplication (or addition) shows that the order the numbers are multiplied it irrelevant, more specifically in the manners of parentheses.
So, the answer is A, which can also be seen in that substituting a as 5, b as 3, and c as 6 gives us the first example.
