2 years ago

There are twice as many Robins has blue jays and their 21 altogether how many blue jays are there

1 answer:

5 0

R + b = 21
2b = r

now we sub eq 2 into eq 1
r + b = 21
2b + b = 21
3b = 21
b = 21/3
b = 7

2b = r
2(7) = r
14 = r

so there are 7 bluejays (b) and 14 robins (r)...for a total of 21

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