A pet shop has only birds and dogs.If there are 30 pets and they have a total of 86 legs, how many of the pets are birds?
no
To answer this question, we need to set up a system of equations based on the given information. Let's say the number of birds is represented by 'b' and the number of dogs is represented by 'd'. We know that there are a total of 30 pets, so we can write the first equation as:
b + d = 30 ---(Equation 1)
We also know that the total number of legs is 86. Since dogs have 4 legs and birds have 2 legs, we can write the second equation as:
4d + 2b = 86 ---(Equation 2)
Now, we can solve these two equations simultaneously to find the values of 'b' and 'd'.
First, let's rewrite Equation 1 in terms of one variable:
b = 30 - d
Now, substitute this value of 'b' into Equation 2:
4d + 2(30 - d) = 86
Simplifying this equation:
4d + 60 - 2d = 86
Combining like terms:
2d + 60 = 86
Subtracting 60 from both sides:
2d = 26
Dividing both sides by 2:
d = 13
Now we can substitute the value of 'd' back into Equation 1 to find the value of 'b':
b + 13 = 30
b = 30 - 13
b = 17
So, there are 17 birds and 13 dogs in the pet shop.
if the dogs are four legged, and birds two, then
2B+4D=86
B+D=30
can you take it from here?