Answer:
C
Step-by-step explanation:
<h3>Answer:</h3>
Equation of the ellipse = 3x² + 5y² = 32
<h3>Step-by-step explanation:</h3>
<h2>Given:</h2>
- The centre of the ellipse is at the origin and the X axis is the major axis
- It passes through the points (-3, 1) and (2, -2)
<h2>To Find:</h2>
- The equation of the ellipse
<h2>Solution:</h2>
The equation of an ellipse is given by,
Given that the ellipse passes through the point (-3, 1)
Hence,
Cross multiplying we get,
- 9b² + a² = 1 ²× a²b²
- a²b² = 9b² + a²
Multiply by 4 on both sides,
- 4a²b² = 36b² + 4a²------(1)
Also by given the ellipse passes through the point (2, -2)
Substituting this,
Cross multiply,
- 4b² + 4a² = 1 × a²b²
- a²b² = 4b² + 4a²-------(2)
Subtracting equations 2 and 1,
- 3a²b² = 32b²
- 3a² = 32
- a² = 32/3----(3)
Substituting in 2,
- 32/3 × b² = 4b² + 4 × 32/3
- 32/3 b² = 4b² + 128/3
- 32/3 b² = (12b² + 128)/3
- 32b² = 12b² + 128
- 20b² = 128
- b² = 128/20 = 32/5
Substituting the values in the equation for ellipse,
Multiplying whole equation by 32 we get,
3x² + 5y² = 32
<h3>Hence equation of the ellipse is 3x² + 5y² = 32</h3>
Answer:
165km
Step-by-step explanation:
If Gina leaves now and drives at 66km/h she will reach Alton just in time for her appointment
Now:
Distance=Speed X Time
D=66 X t=66t.....(I)
If she leaves in 40 minutes,and she must get there at the same time, her new drive time will be:
t hours - 40 minutes
=(t-40/60)hours=( t-2/3) hours
Her Distance this time
D=90(t-2/3)=90t-60.....(ii)
Since the distance to Alton does not change, we equate (I) and (ii)
66t=90t-60
60=90t-66t
60=24t
t=2.5 hours
From equation (I)
Distance=66t=66X2.5=165km
Distance to Alton is 165km.
107360 yards = 31 miles = 1 hour
1 second = 1789.3333333 yards
x-3y= 1
The equation needs to be rewritten in proper Slope intercept form ( y = mx+b) where m is the slope and b is the y-intercept.
x-3y = 1
Subtract x from each side:
-3y = 1-x
Divide both sides by -3:
y = 1/-3 - x/-3
Simplify:
y = 1/3x - 1/3
The slope is 1/3