The rationals being closed under subtraction means that if we start with two rational numbers and subtract them, we get another rational number. Choice c subtracts two rational numbers but gets the wrong answer, so isn't support for anything. Choice b is rational too because the square root of 4 is 2.
Answer: b
1. added four to both sides
2. divided both sides by two
Answer:the length of each side of the larger square is 6 centimeters.
Step-by-step explanation:
Let x represent the length of each side of the small square.
Let y represent the length of each side of the Large square.
The area of the small square is x^2
The area of the large square is y^2
The combined area of two squares is 45 square centimeters. This means that
x^2 + y^2 = 45 - - - - - - - - - - -1
Each side of one square is twice as long as a side of the other square. This means that
y = 2x
Substituting y = 2x into equation 1, it becomes
x^2 + (2x)^2 = 45
x^2 + 4x^2 = 45
5x^2 = 45
x^2 = 45/5 = 9
x = √9 = 3
Substituting x = 3 into y = 2x, it becomes
y = 2 × 3 = 6 centimeters
Answer:
DE/AB= DC/AC , 12/AB= 6/11 , AB= 12×11/6=2×11=22 , Sory i can't explain , i bad know english language. or so ABC~CDE because DE||AB=> DE/AB=DC/AC
D. 300 it is. is there more?
