Answer: 4.2495 feets
Step-by-step explanation:
Given the following :
Rate of change (speed) when rock hits the lake surface = - 3in/s
Distance or depth after 5 seconds :
Distance = rate of change * time
Distance = (- 3 in/s × 5) = - 15 inches
1 inch = 0.0833 feet
15 inches = (-15 * 0.0833) = - 1.2495 feets
Distance between Lisa's hand and lake surface = 3 feets :
Distance between Lisa's hand and rock after 5 seconds :
(3 feets + 1.2495 feets) = 4.2495 feets
See the photo attached. The boxed answer is the corrected answer
The answer is equal to (B). The solutions are x = -7.7 and x = -1.3.
Since they are right triangles use Pythagorean Theorem.
a^2 + b^2 = c^2 where c is the hypotenuse.
a. 12^2 + b^2 = 13^2
144 + b^2 = 169
subtract 144 from both sides
b^2 = 25
take the square root of both sides
t = 5 This is also know as a Pythagorean Triple 5-12-13
b. a^2 + 9^2 = 12^2
a^2 + 81 = 144
subtract 81 from both sides
a^2 = 63
take the square root of both sides
a = √63
a = √(9 * 7)
a = 3√7
c. 6^2 + 9^2 = c^2
36 + 81 = c^2
117 = c^2
take the square root of each side
c = √117
c = √(9*13)
x = 3√13