Answer:
25x² − 20x + 4
Explanation:
(5x − 2)²
= (5x + −2)(5x + −2)
= (5x)(5x) + (5x)(−2) + (−2)(5x) + (−2)(−2)
= 25x² − 10x − 10x + 4
= 25x² − 20x + 4
Answer:
Blank 1: 40
Blank 2: 10
Step-by-step explanation:
You can start by representing the speed of the water as x and the speed of the dolphin as y, and writing an equation.
y+x=50
y-x=30
Adding these two equations together, you get:
2y=80
y=40 for the speed of the dolphin in still water. Now, you an use one of the previous equations to find the speed of the current.
40-x=30
x=10
Hope this helps!
x^2b + t = x^2e
x^2e - x^2b = t
x^2(e - b) = t
x^2 = t /(e -b)
x = √[t /(e -b)] or x = - √[t /(e -b)]