The equation represents 21 seats and 30 wheels will be given as B.
u + 2b = 30
It is defined as the relation between two variables, if we plot the graph of the linear equation we will get a straight line.
The owner of a bike shop sells unicycles and bicycles and keeps inventory by counting seats and wheels. One day, she counts 21 seats and 30 wheels.
u is the number of unicycles and b is the number of bicycles.
There are total 21 seats
⇒ u+b=21
unicycle has 1 wheel and bicycle has 2 and total there are 30 wheels
⇒ u+2b=30
Hence,the equation represents 21 seats and 30 wheels will be given as B. u + 2b = 30
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