You can do trial and error to all of the choices. They are presented as coordinates (x,y). Just substitute the x and y values, then if they satisfy the equation, then that is the answer. Among the choices, the answer would be B. Here's why:
x = 3, y = 4
2(3) + 4 > 8
10 > 8 TRUE
3 - 4 < 2
-1 < 2 TRUE
Thus, the answer is B.
Answer:
See below.
Step-by-step explanation:
(a) Because the solution led to a square root of a negative number:
x^2 -10x+40=0
x^2 - 10x = -40 Completing the square:
(x - 5)^2 - 25 = -40
(x - 5)^2 = -15
x = 5 +/-√(-15)
There is no real square root of -15.
(b) A solution was found by introducing the operator i which stands for the square root of -1.
So the solution is
= 5 +/- √(15) i.
These are called complex roots.
(c) Substituting in the original equation:
x^2 - 10 + 40:
((5 + √(-15)i)^2 - 10(5 + √(-15)i) + 40
= 25 + 10√(-15)i - 15 - 50 - 10√(-15)i + 40
= 25 - 15 - 50 + 40
= 0. So this checks out.
Now substitute 5 - √(-15)i
= 25 - 10√(-15)i - 15 - 50 + 10√(-15)i + 40
= 25 - 15 - 50 + 40
= 0. This checks out also.
Answer:
5 miles
Step-by-step explanation:
This is because if you draw a line going west and label it as 4 miles, then draw another line going south and label it 3 miles, you form a right angle, right? So, the fastest way to go back would be taking a diagonal-like route back to the beginning. Does this shape look familiar to you? Right! It's a right triangle. And do the numbers 3, 4, and 5 sound familiar to you? Yup, it's a Pythagorean triplet. If the legs of a right triangle are 3 and 4, the hypotenuse is 5. Why am I saying this? Because, in the drawing you just did, the 4 miles west and 3 miles south were the legs, and the diagonal path back to the beginning is the hypotenuse. Get it now?
Happy to help! :)
Answer:90
Step-by-step explanation:
