54*10 to the 3rd power equals 5'400
His total sales were "x"
now, we know that 3.5% of "x" plus 5% of "x", will add up to his total commission, including sales of 6500 or less or more
so the commission for 6500 or less, is 3.5% of "x" or (3.5/100)*x -> 0.035x
the commission for above 6500 is 5% or (5/100) * x --> 0.05x
we know, that both commissions added together, are $415
thus
0.035x + 0.05x = 415 <----- solve for "x"
Since they're vertical angles, they're equal in degree measure
since they're equal, we can make the two expressions equal to each other
5a - 1 = 2a + 20
add 1 to both sides
5a = 2a + 21
subtract 2a from both sides
3a = 21
divide both sides by 3a
a = 7
now, plug the answer you found for a into one of the two expressions
5a - 1 becomes (5*7) - 1, which equals 34
to double check that they're equivalent (since they're vertical angles)
2a + 20 becomes (2*7) + 20, which equals 34
both angles are 34 degrees!
15 + 4(h) = 27
27 - 15 = 12
12/4 = 12
Margie can rent the bicycle for 4 hours.
