Answer:
0
Step-by-step explanation:
So we have the expression:
And we want to evaluate it for x=-4 and y=8.
So, substitute:
Multiply:
Add:
Evaluate:
So, our answer is 0.
And we're done!
Answer:
c = 8
Step-by-step explanation:
Given the following data;
Slope, m = -2
Points (x, y) = (5, -2)
To find the intercept, c;
Equation of a straight line is given by the formula: y = mx + c
Where;
m is the slope.
x and y are the points
c is the intercept.
Substituting the values in order to find the intercept, we have;
-2 = -2(5) + c
-2 = -10 + c
c = 10 - 2
c = 8
Therefore, the y-intercept is 8.
Answer:
13 ft/s
Step-by-step explanation:
t seconds after the boy passes under the balloon the distance between them is ...
d = √((15t)² +(45+5t)²) = √(250t² +450t +2025)
The rate of change of d with respect to t is ...
dd/dt = (500t +450)/(2√(250t² +450t +2025)) = (50t +45)/√(10t² +18t +81)
At t=3, this derivative evaluates to ...
dd/dt = (50·3 +45)/√(90+54+81) = 195/15 = 13
The distance between the boy and the balloon is increasing at the rate of 13 ft per second.
_____
The boy is moving horizontally at 15 ft/s, so his position relative to the spot under the balloon is 15t feet after t seconds.
The balloon starts at 45 feet above the boy and is moving upward at 5 ft/s, so its vertical distance from the spot under the balloon is 45+5t feet after t seconds.
The straight-line distance between the boy and the balloon is found as the hypotenuse of a right triangle with legs 15t and (45+5t). Using the Pythagorean theorem, that distance is ...
d = √((15t)² + (45+5t)²)
The statement is always true because right angles measure 90 degrees and if you add them you get 180 and supplementary angles are angles that add up to 180.
Hope this helps :)
Answer:
d
Step-by-step explanation:
Try using simple numbers like 1 as x and then try with the different functions until it works