Given:
a square with an area of a² is enlarged to a square with an area of 25a².
The side length of the smaller square was changed when The side length was multiplied by 5.
Area = (1a)² = a²
Area = 1a * 5 = 5a ⇒ (5a)² = 25a²
For this case we have that the variable "x" represents the number of hours that Leticia uses to take care of children on Saturday.
IF on Friday I use 4 hours ($ 8 each) and on Saturday "x" hours ($ 8 each) obtaining a profit of $ 72, we have the following equation:

We apply distributive property:

So, on Saturday she spent 5 hours.
Answer:

<span>the equation -2x² + 5x -3=0, we notice that the sum of the coefficient equals 0, -2+5-3=0, if such a case happens, the solution of the previous equation will be, x=1 (always) and x= c/a, a=-2, and c=-3, so x=-3/-2, finally, the answer is: the 2 in the denominator should be -2</span>
Answer:
20n² - 40n + 20
Step-by-step explanation:
(5n - 5)(4n - 4)
= 5n(4n) + 5n(-4) - 5(4n) - 5(-4)
= 20n² - 20n - 20n + 20
= 20n² - 40n + 20
Another way to do this:
(5n - 5)(4n - 4)
= 5(n - 1) * 4(n - 1)
= 20(n - 1)(n - 1)
= 20(n - 1)²
= 20(n² - 2n + 1)
= 20n² - 40n + 20