Answer:
Step-by-step explanation:
6x + y = 30
-6x - 15y = 54
-14y = 84
y = -6
6x - 6 = 30
6x = 36
x = 6
(6, -6)
You are gonna use a^2 + b^2 = c^2 because the cities make a right triangle and you are trying to find the hypotenuse (c). C^2 ends up being 517 and the square root, your answer, is 22.7 miles
The simple way of calculating a perimeter is to add all of the sides.
For a rectangle this would equal 2 x length + 2 x width
P = 2(6x + 3) + 2(-2x - 5)
= 12x + 6 - 4x - 10
= 8x - 4
At a higher level both the length and width must be greater than zero (= zero is a trivial rectangle)
6x + 3 > 0
6x > -3
x > -0.5
-2x - 5 > 0
2x + 5 < 0 (multiplying by -1 reverses the inequality)
2x < -5
x < -2.5
This rectangle cannot exist as x cannot be < -2.5 and > -0.5 at the same time!
Answer:

Step-by-step explanation:

10² - 2 (8) + 11 . Use PEMDAS, which is the order of operation to follow:
P = parenthesis → 10² - 2x8 +11
E = exponent → 100 - 2x8 +11
M = Multiplication → 100 -16 +11
D = Division → NO DIVISION
A = Addition → 111 -16
S = Subtraction → 95 (answer 3)
Apply the same logic for the 2nd exercice and you will find 26 (I don't see the 26 in your answer but I am sure it's 26)