Answer:
the third one

Step-by-step explanation:
<span>b – 2a – c
= 9 - 2(-3) - (-6)
= 9 + 6 + 6
= 21
answer
21</span>
Answer:
Answer (B) and (D)
Step-by-step explanation:
First we need to figure out: What is quadrant II about?
As said in the picture provided, quadrant II is in the upper left corner of a graph.
For a point to be in QII, the <em>x values need to be negative</em>, and <em>the y values need to be positive</em>.
B: (-4,2) and D: (-3,5) would belong in QII.
<em>Their x values are negative, and the y values are positive. </em>
<em>Therefore, </em><em>B and D would be the correct answers.</em>
<em />
Answer: 80 miles for the first ship, and 150 miles for the other.
Explanation:
First thing we should do is correspond each number with a letter:
Let x be the distance travel by ship heading east
Let y be the distance travel by ship heading south
y = x + 70 -- (1)
sqrt(x^2 + y^2) = 170 -- (2)
Subtract (1) into (2):
sqrt(x^2 + (x + 70)^2) = 170
x^2 + x^2 + 140x + 4900 = 28900
2x^2 + 140x - 24000 = 0
x ^2 + 70x - 12000 = 0
(x - 80)(x + 150) = 0
x = 80 or -150
Since the distance for the first ship can’t be negative, therefore, x = 80 -- (3)
Subtract (3) into (1), therefore, y = 150
Hope this helps! :)