Let Jean's speed while running = x mph
Then Jean's speed while riding will be = x+9 mph
Distance covered by running = 8 miles
Distance covered by riding = 11 miles
Total time taken to complete the race = 1.5 hours
As, 
So, time for running= 
And time for riding= 
Equation becomes:

Now, multiply every term by 2x(x+9) to clear denominators:

Simplifying it we get

Solve the quadratic equation using formula

putting a=3 , b= -11, c= -144
we get (x - 9)(3x + 16) = 0
where x=9 and x=
Neglect the negative answer as speed cannot be negative, so x = 9 mph
Hence, Jean's running speed is 9 mph and riding speed is x+9 = 9+9 = 18 mph
Answer:
76
Step-by-step explanation:
recall that for a quadratic equation in the form
ax² + bx + c = 0, the discriminant is given by
discriminant, D = b²- 4ac
we are given the following:
-6x² + 2x + 3 = 0,
comparing this with the general equation above, it is clear that,
a = -6, b = 2 and c = 3,
substituting these into our equation for discriminant:
D = b²- 4ac
= 2² - 4(-6)(3)
= 4 + 72
= 76
15 percent of the fruit in the fruit bowl are oranges
Answer:
b
Step-by-step explanation:
Answer:
4 mile= 40
12 mile= 120
it will take him 80
Step-by-step explanation: