Y = a (x + 3)² - 1
Let's take the point (-1;3)
3 = a ( -1 + 3)² - 1
3 = 4a - 1
4a = 4
Therefore a = 4/4 = 1
(x+3)² - 1
= x² + 6x + 9 - 1
= x² + 6x + 8
The answer would be y = x² + 6x + 8.
Hope this helps !
Photon
374 = 33
272 = x
374/33 = 272/x
x=(33*272)/374=24 minutes
1.7=2
8.1=8
6.9=7
4.3=4
Hope this helps
This Question is related to Direct Proportionality
Here : The Number of Miles Driven is Directly Proportional to Number of Gallons of Gas
Number of Miles ∝ Gallons of Gas
Given Keith with 16 Gallons of Gas Drove 436 Miles
⇒ Keith with 1 Gallon of Gas would Drive -
Miles
⇒ Keith with 1 Gallon of Gas would Drive : 27.25 Miles
⇒ Keith with 14 Gallons of Gas would Drive : 14 × 27.25 Miles
⇒ Keith with 14 Gallons of Gas would Drive : 381.5 Miles
<span>Let x = the miles Jeanie ran
y = the miles Jeanie biked
T = 2 hours total time for the duathlon
v1 = 8.5 mph Jeanie's running speed and
v2 = 16 mph Jeanie's biking speed
But T = Jean's time she ran t1 + time she biked t2 I. e t1 + t2 = 2
So we have average speed v2 when she biked = distance (y) / time (t2)
Distance y = v2 * t2 = 16 * t2 and distance when she ran x = 8.5 * t1
Since she covered 27 miles while running and biking we have
x + y = 27
8.5t1 + 16t2 =27 ------(1)
t1 + t2 = 2 --------------(2)
The simultaneous equation gives us
t1 = 2/3 and t2 which is time she biked = 4/3
So 4/3 = 1 1/3. Which is 1 hour 20 minutes</span>