Answer:
1. 
2. 
Step-by-step explanation:
Given
Variation: inverse Proportion
y = 7, x = 9
Required
- Write an equation connecting y and x
- Find y when x = 21
Given that thee variation is inversely proportional;
This implies that
Convert variation to equation
----------- Equation 1
Where k is the constant of variation
Substitute 7 for y and 9 for x in equation 1
Multiply both sides by 9
Substitute 63 for k in equation 1
Multiply both sides by x
Hence, the equation connecting x and y is
Solving for when x = 21
Substitute 21 for x in the above equation
Divide both sides by 21
Answer:
vertex is at (0,0)
Step-by-step explanation:
Find the vertex of the parabola y = 8x2.
I assume you meant y = 8* x^2
this can be compared to the general vertex form y = a (x - h)^2 + k
where vertex at (h, k)
so then...
h =0 and k = 0 here
vertex is at (0,0)
Step-by-step explanation:
The upstream speed is S / t₁, and the downstream speed is S / t₂.
If we say f is the speed of the fish in calm water, and r is the speed of the river, then:
f − r = S / t₁
f + r = S / t₂
If we say T is the time it takes to cross the river, then the speed perpendicular to the river is ℓ/T, the speed parallel to the river is r, and the overall speed is f.
Using Pythagorean theorem:
f² = (ℓ/T)² + r²
f² − r² = (ℓ/T)²
(f − r) (f + r) = (ℓ/T)²
(S / t₁) (S / t₂) = (ℓ/T)²
S² / (t₁ t₂) = (ℓ/T)²
(t₁ t₂) / S² = (T/ℓ)²
√(t₁ t₂) / S = T/ℓ
T = ℓ√(t₁ t₂) / S
3 / (1/8) = 3 × (8/1) = 24
There needs to be 24 students on a team.
