Answer:
A
Step-by-step explanation:
Given
y - 2x - 8 = 0 ( add 2x + 8 to both sides )
y = 2x + 8 → (1)
y² + 8x = 0 → (2)
Substitute y = 2x + 8 into (2)
(2x + 8)² + 8x = 0 ← expand left side using FOIL and simplify
4x² + 32x + 64 + 8x = 0
4x² + 40x + 64 = 0 ( divide through by 4 )
x² + 10x + 16 = 0 ← in standard form
(x + 8)(x + 2) = 0 ← in factored form
x + 8 = 0 ⇒ x = - 8
x + 2 = 0 ⇒ x = - 2
Substitute these values into (1) for corresponding values of y
x = - 8 : y = 2(- 8) + 8 = - 16 + 8 = - 8 ⇒ P (- 8, - 8)
x = - 2 : y = 2(- 2) + 8 = - 4 + 8 = 4 ⇒ Q (- 2, 4 )
Calculate the length of PQ using the distance formula
PQ = 
with (x₁, y₁ ) = P (- 8, - 8) and (x₂, y₂ ) = Q (- 2, 4 )
PQ = 
= 
= 
= 
= 
= 
= 
× 
= 6 → A
Answer:
20 : 16
or if you have to reduce then the answer is 5 : 4
Step-by-step explanation:
Answer:
4Joules
Step-by-step explanation:
According to Hooke's law which states that extension of an elastic material is directly proportional to the applied force provide that the elastic limit is not exceeded. Mathematically,
F = ke where
F is the applied force
K is the elastic constant
e is the extension
If a spring exerts a force of 6 N when stretched 3 m beyond its natural length, its elastic constant 'k'
can be gotten using k = f/e where
F = 6N, e = 3m
K = 6N/3m
K = 2N/m
Work done on an elastic string is calculated using 1/2ke².
If the spring is stretched 2 m beyond its natural length, the work done on the spring will be;
1/2× 2× (2)²
= 4Joules
Find the pattern first which is multiply by 5. This problem is geometric sequence so you have to use this formula to find the 10th term:
An=AR^n-1
A(10)=0.1(5)^(10-1)
A(10)=195312.5
