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.
Trying to factor by splitting the middle term
Factoring <span> b2-4b+4</span>
The first term is, <span> <span>b2</span> </span> its coefficient is <span> 1 </span>.
The middle term is, <span> -4b </span> its coefficient is <span> -4 </span>.
The last term, "the constant", is <span> +4 </span>
Step-1 : Multiply the coefficient of the first term by the constant <span> 1 • 4 = 4</span>
Step-2 : Find two factors of 4 whose sum equals the coefficient of the middle term, which is <span> -4 </span>.
<span><span> </span></span>
<span><span>-4 + -1 = -5</span><span> -2 + -2 = -4 That's it</span></span>
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -2 and -2
<span>b2 - 2b</span> - 2b - 4
Step-4 : Add up the first 2 terms, pulling out like factors :
b • (b-2)
Add up the last 2 terms, pulling out common factors :
2 • (b-2)
Step-5 : Add up the four terms of step 4 :
(b-2) • (b-2)
Which is the desired factorization
Answer:
7i..........................
2.5*7 = 17.5. If it's easier for you, multiply 2.5 by 5 then add 2.5*2.
Answer:
- 2, 0 or 4
Step-by-step explanation:
y = x(x - 4)(x + 2)
x' = 0
x - 4 = 0
x" = 4
x + 2 = 0
x"' = - 2
I hope I helped you.
