Respuesta :

Let x the number of bikes, and y the number of trikes. 
We have the equations:
x+y=7 (only one seat )
2x+3y=19 (two wheels for a bikes and three wheels for each trike)
Solving the above system for x and y we get:
x=2, y=5. 
So there are two bikes and 5 wheels. 
For solving, use x = 7-y, then using the second equation 
2(7-y)+3y=19. solving the above equation for y we get y=5 then 
deduce x=7-y=7-5=2. 
hisroyal1

Answers:

There are 2 bikes there

There are 5 trikes there

 

EXPLANATION

Let the number of bikes be represented by b

Let the number of trikes be represented by t

 

 

Given,

There are a total of 7 seats

We know that each bike and each trike has only a seat,

Therefore, b + t = 7                                        … (Equation I)

 

Given,

There are a total of 19 wheels.

We know that each bike has 2 wheels

And each trike has 3 wheels

Therefore, 2b + 3t = 19                                 … (Equation II)

 

b + t = 7                               … (Equation I)

b = 7 – t                               … (Equation III)

 

Substitute 7 – t for b in equation II

2b + 3t = 19                                       … (Equation II)

2(7 – t) + 3t = 19

14 – 2t + 3t = 19

14 + t = 19

 

Subtract 14 from both sides of the equation

14 + t = 19

14 – 14 + t = 19 – 14

t = 5

Therefore, there are 5 trikes

 

To find the value of b, substitute 5 for t in Equation III

b = 7 – t                               … (Equation III)

b = 7 – 5

b = 2

Therefore, there are 2 bikes

Otras preguntas