Answer: 5 or c
Step-by-step explanation:
Casey is 18 years old and Ralph is 3 years old.
Step-by-step explanation:
Let,
Age of Casey = x
Age of Ralph = y
According to given statement;
x = 6y Eqn 1
In two years
x+2=4(y+2)
x+2=4y+8
x = 4y+8-2
x = 4y+6 Eqn 2
Putting value of x from Eqn 1 in Eqn 2

Dividing both sides by 2

Putting y=3 in Eqn 1

Casey is 18 years old and Ralph is 3 years old.
Keywords: word problems, substitution method
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507 i think. you just square 13 then multiply that by pi which is 3
Answer:
18x+63
Step-by-step explanation:
First you've to simplfy it, multiply the first bracket by 5 and the second by 4.
= (5)(2x)+(5)(7) + (4)(2x)+(4)(7)
= 10x+35+8x+28
Combine Like Terms:
= 10x+35+8x+28
= (10x+8x)+(35+28)
= 18x+63
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